N,n-disubstituted aminoalkylbiphenyl antagonists of prostaglandin d2 receptors

ABSTRACT

Described herein are compounds that are antagonists of PGD 2  receptors. Also described are pharmaceutical compositions that include the compounds described herein, and methods of using such antagonists of PGD 2  receptors, alone or in combination with other compounds, for treating respiratory, cardiovascular, and other PGD 2 -dependent or PGD 2 -mediated conditions or diseases.

RELATED APPLICATIONS

This application claims the benefit of U.S. provisional patent application No. 61/025,597 entitled “N,N-disubstituted aminoalkylbiphenyl antagonists of prostaglandin D2 receptors” filed on Feb. 1, 2008 and U.S. provisional patent application No. 61/110,496 entitled “N,N-disubstituted aminoalkylbiphenyl antagonists of prostaglandin D2 receptors” filed on Oct. 31, 2008, all of which are incorporated by reference in their entirety.

FIELD OF THE INVENTION

Described herein are compounds, methods of making such compounds, pharmaceutical compositions comprising such compounds, and methods of using such compounds to treat, prevent or diagnose diseases or conditions associated with prostaglandin D₂.

BACKGROUND OF THE INVENTION

Prostaglandins have a diverse range of activities and have a well recognized role in pain and inflammation. Prostaglandin D₂ (PGD₂) is produced by mast cells, macrophages and T_(H)2 lymphocytes in response to local tissue damage as well as allergic inflammation in diseases such as asthma, rhinitis, and atopic dermatitis. PGD₂ binds to a number of receptors, which include the thromboxane-type prostanoid (TP) receptor, PGD₂ receptor (DP, also known as DP₁) and chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2; also known as DP₂).

SUMMARY OF THE INVENTION

Presented herein are compounds, pharmaceutical compositions, and methods, for (a) diagnosing, preventing, or treating allergic and non-allergic inflammation, (b) mitigating adverse signs and symptoms that are associated with inflammation, and/or (c) controlling immunological, proliferative disorders. These disorders may arise from one or more of a genetic, iatrogenic, immunological, infectious, oncological, toxic, surgical, and/or traumatic etiology. In one aspect, the methods, compounds, pharmaceutical compositions, and medicaments described herein comprise antagonists of PGD₂ receptors. In one aspect, the methods, compounds, pharmaceutical compositions, described herein comprise antagonists of DP₂.

In one aspect provided herein are compounds of Formula (I), pharmaceutically acceptable salts, pharmaceutically acceptable prodrugs, and pharmaceutically acceptable solvates thereof, which are antagonists of DP₂, and are used to treat mammals suffering from one or more PGD₂-dependent conditions or diseases, including, but not limited to, asthma, rhinitis, allergic conjuctivitis, atopic dermatitis, chronic obstructive pulmonary disease (COPD), pulmonary hypertension, interstitial lung fibrosis, arthritis, allergy, psoriasis, inflammatory bowel disease, adult respiratory distress syndrome, myocardial infarction, aneurysm, stroke, cancer, wound healing, endotoxic shock, pain, inflammatory conditions, eosinophilic esophagitis, eosinophil-associated gastrointestinal disorders (EGID), idiopathic hypereosinophilic syndrome, otitis, airway constriction, mucus secretion, nasal congestion, increased microvascular permeability and recruitment of eosinophils, urticaria, sinusitis, angioedema, anaphylaxia, chronic cough and Churg Strauss syndrome.

In one aspect, provided is a compound having the structure of Formula (I) or pharmaceutically acceptable salt thereof:

wherein,

-   -   R⁴ is H, halogen, —CN, —OH, C₁-C₄alkyl, C₁-C₄alkoxy,         C₁-C₄fluoroalkyl, C₁-C₄fluoroalkoxy, or C₁-C₄heteroalkyl;     -   R⁵ is H, halogen, CN, —NO₂, —OH, —S(═O)₂R¹², —NHS(═O)₂R¹²,         —C(═O)R¹², —OC(═O)R¹², —CO₂R¹³, —N(R¹³)₂, —C(═O)N(R¹³)₂,         —NHC(═O)R¹², —C(OH)(R¹³)₂, C₁-C₄alkyl, C₁-C₄fluoroalkyl,         C₁-C₄fluoroalkoxy, C₁-C₄alkoxy, C₁-C₄heteroalkyl, or —S—R¹²;     -   R²⁰ is C₁-C₄alkyl, C₃-C₆cycloalkyl, —CH₂O—C₁-C₄alkyl,         —CH₂O-(substituted or unsubstituted phenyl),         —CH(CH₃)—O-(substituted or unsubstituted phenyl),         —C(CH₃)₂—O-(substituted or unsubstituted phenyl),         —CH₂OCH₂-(substituted or unsubstituted phenyl), —OC₁—C₄alkyl,         —O—CH₂-(substituted or unsubstituted phenyl),         —O—CH(CH₃)-(substituted or unsubstituted phenyl),         —NR¹⁶C₁-C₄alkyl, —NR¹⁶—CH₂-(substituted or unsubstituted         phenyl), or —NR¹⁶—CH(CH₃)-(substituted or unsubstituted phenyl),         wherein if the phenyl of R²⁰ is substituted, then the phenyl is         substituted with 0, 1, or 2 R²¹ groups;         -   each R²¹ is independently selected from halogen, —OH, —OCH₃,             C₁-C₄alkyl, and —CF₃;         -   R¹⁶ is H or C₁-C₄alkyl;     -   R¹¹ is —CH₃, —CH₂CH₃, —CF₃, —CH₂CF₃, cyclopropyl, cyclobutyl, or         cyclopentyl     -   R¹² is C₁-C₄alkyl, C₁-C₄heteroalkyl, or C₁-C₄fluoroalkyl;     -   each R¹³ is independently selected from H, C₁-C₄alkyl,         C₁-C₄heteroalkyl, and C₁-C₄fluoroalkyl.

In one aspect, presented herein are the compounds of Formula (I) presented in Table 1, or pharmaceutically acceptable salts, pharmaceutically active metabolites, pharmaceutically acceptable prodrugs, and pharmaceutically acceptable solvates thereof.

Compounds of Formula (I) are antagonists of DP₂.

In one aspect, provided herein are pharmaceutical compositions comprising a therapeutically effective amount of a compound of Formula (I). In some embodiments, the pharmaceutical compositions comprise at least one inactive pharmaceutically acceptable inactive ingredient selected from excipients, diluents, and carriers.

In certain embodiments, presented herein are methods for treating a PGD₂-dependent condition or disease in a mammal comprising administering to the mammal a therapeutically effective amount of a compound of Formula (I).

In another aspect, compounds of Formula (I) are used to treat or prevent inflammatory diseases or conditions. Inflammatory conditions include, but are not limited to, asthma, rhinitis, chronic obstructive pulmonary disease, pulmonary hypertension, interstitial lung fibrosis, atherosclerosis, aortic aneurysm, myocardial infarction, and stroke.

In a specific aspect, provided herein is a method for treating asthma in a mammal comprising administering a therapeutically effective amount of a compound provided herein to the mammal in need.

In another aspect, compounds of Formula (I) are used to treat or prevent immunological disorders, including, but are not limited to, allergy or to excessive or inappropriate response to an endogenous or exogenous antigen. In certain embodiments, the immunological disorder that is characterized by immune dysregulation that is not accompanied by inflammation.

In additional aspects, such diseases or conditions are iatrogenic and increases in, or abnormal localization of, PGD₂ is induced by other therapies or medical or surgical procedures. In other embodiments, the PGD₂-dependent or PGD₂ mediated condition or disease is caused by surgery.

In another aspect are methods for treating respiratory diseases or conditions in a mammal comprising administering to the mammal at least once an effective amount of at least one compound of Formula (I). In a further embodiment of this aspect, the respiratory disease is asthma. In a further embodiment of this aspect, the respiratory disease includes, but is not limited to, asthma, adult respiratory distress syndrome, allergic (extrinsic) asthma, non-allergic (intrinsic) asthma, acute severe asthma, chronic asthma, clinical asthma, nocturnal asthma, allergen-induced asthma, aspirin-sensitive asthma, exercise-induced asthma, neutrophillic asthma, isocapnic hyperventilation, child-onset asthma, adult-onset asthma, cough-variant asthma, occupational asthma, steroid-resistant asthma, seasonal asthma, seasonal allergic rhinitis, perennial allergic rhinitis, chronic obstructive pulmonary disease, including chronic bronchitis or emphysema, pulmonary hypertension, interstitial lung fibrosis and/or airway inflammation and cystic fibrosis, and hypoxia.

In another aspect compounds described herein are used for treating rhinitis in a mammal. In a further embodiment of this aspect, compounds described herein are used for treating allergic (extrinsic) rhinitis, non-allergic (intrinsic) rhinitis, chronic rhinitis, allergen-induced rhinitis, aspirin-sensitive rhinitis, child-onset rhinitis, adult-onset rhinitis, occupational rhinitis, steroid-resistant rhinitis, seasonal rhinitis, perennial rhinitis, rhinosinusitis, and rhinopolyposis.

In another aspect are methods for treating chronic obstructive pulmonary disease comprising administering to the mammal at least once an effective amount of a compound of Formula (I). In a further embodiment of this aspect, chronic obstructive pulmonary disease includes, but is not limited to, chronic bronchitis and/or emphysema, pulmonary hypertension, interstitial lung fibrosis and/or airway inflammation and cystic fibrosis.

In another aspect are methods for preventing increased mucosal secretion and/or edema in mammals comprising administering to the mammal at least once an effective amount of a compound of Formula (I).

In another aspect are methods for preventing eosinophil and/or basophil and/or dendritic cell and/or neutrophil and/or monocyte or TH2 cell recruitment comprising administering to the mammal an effective amount of a compound of Formula (I).

In another aspect are methods for treating or preventing ocular inflammation, conjunctivitis, retinitis, scleritis, uveitis, allergic conjunctivitis, vernal keratoconjunctivitis, and papillary conjunctivitis comprising administering to the mammal at least once an effective amount of a compound of Formula (I).

In another aspect, compounds of Formula (I) are used to treat or prevent pain.

In another aspect are methods for preventing or treating acute or chronic disorders involving recruitment or activation of eosinophils comprising administering to the mammal at least once an effective amount of a compound of Formula (I).

In another aspect are methods for treating inflammatory responses of the skin comprising administering to the mammal at least once an effective amount of at least one compound of Formula (I). Such inflammatory responses of the skin include, by way of example, psoriasis, dermatitis, atopic dermatitis, contact dermatitis, eczema, urticaria, rosacea, bullous disorders, collagenoses, Kawasaki Disease, Sjogren-Larsso Syndrome, urticaria, wound healing and scarring. In another aspect are methods for reducing psoriatic lesions in the skin, joints, or other tissues or organs, comprising administering to the mammal an effective amount of a compound of Formula (I). In another aspect are methods for reducing psoriatic lesions in the skin, joints, or other tissues or organs, comprising administering at least once to the mammal an effective amount of a compound of Formula (I).

In a further aspect are methods to modulate the immune response to endogenous or exogenous antigens. In a further aspect are methods to treat acute or chronic allergic responses to exogenous substances that have been ingested such as foods (e.g., peanuts) or drugs (e.g., penicillin, non-steroidal anti-inflammatory drugs or the like).

In another aspect is the use of a compound of Formula (I) in the manufacture of a medicament for treating an inflammatory disease or condition in a mammal in which the activity of at least one PGD₂-associated protein contributes to the pathology and/or symptoms of the disease or condition. In one embodiment of this aspect, the PGD₂ pathway protein is DP2. In another or further embodiment of this aspect, the inflammatory disease or conditions are respiratory, cardiovascular, or proliferative diseases.

“Cardiovascular disease or conditions,” refers to diseases affecting the heart or blood vessels or both, including but not limited to: arrhythmia (atrial or ventricular or both); atherosclerosis and its sequelae; angina; cardiac rhythm disturbances; myocardial ischemia; myocardial infarction; cardiac or vascular aneurysm; vasculitis, stroke; peripheral obstructive arteriopathy of a limb, an organ, or a tissue; reperfusion injury following ischemia of the brain, heart or other organ or tissue; endotoxic, surgical, or traumatic shock; hypertension, valvular heart disease, heart failure, abnormal blood pressure; shock; vasoconstriction (including that associated with migraines); vascular abnormality, inflammation, insufficiency limited to a single organ or tissue.

In any of the aforementioned aspects are further embodiments in which: (a) the effective amount of the compound is systemically administered to the mammal; and/or (b) the effective amount of the compound is administered orally to the mammal; and/or (c) the effective amount of the compound is intravenously administered to the mammal; and/or (d) the effective amount of the compound administered by inhalation; and/or (e) the effective amount of the compound is administered by nasal administration; or and/or (f) the effective amount of the compound is administered by injection to the mammal; and/or (g) the effective amount of the compound is administered topically (dermal) to the mammal; and/or (h) the effective amount of the compound is administered by ophthalmic administration; and/or (i) the effective amount of the compound is administered rectally to the mammal.

In any of the aforementioned aspects are further embodiments comprising single administrations of the effective amount of the compound, including further embodiments in which (i) the compound is administered once; (ii) the compound is administered to the mammal multiple times over the span of one day; (iii) continually; or (iv) continuously.

In any of the aforementioned aspects involving the treatment of PGD₂ dependent diseases or conditions are further embodiments comprising administering at least one additional agent in addition to the administration of a compound having the structure of Formula (I).

In any of the aforementioned aspects involving the prevention or treatment of inflammation are further embodiments comprising: (a) monitoring inflammation in a mammal; (b) measuring bronchoconstriction in a mammal; (c) measuring eosinophil and/or basophil and/or dendritic cell and/or neutrophil and/or monocyte and/or lymphocyte recruitment in a mammal; (d) monitoring mucosal secretion in a mammal; (e) measuring mucosal edema in a mammal.

Other objects, features and advantages of the compounds, methods and compositions described herein will become apparent from the following detailed description. It should be understood, however, that the detailed description and the specific examples, while indicating specific embodiments, are given by way of illustration only, since various changes and modifications within the spirit and scope of the instant disclosure will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1. Illustrative examples of compounds described herein.

FIG. 2. Illustrative examples of compounds described herein.

FIG. 3. Illustrative examples of compounds described herein.

FIG. 4. Illustrative examples of compounds described herein.

FIG. 5. Illustrative examples of compounds described herein.

FIG. 6. Illustrative examples of compounds described herein.

FIG. 7. Illustrative examples of compounds described herein.

DETAILED DESCRIPTION OF THE INVENTION

Prostaglandin D₂ (PGD₂) is an acidic lipid derived from the metabolism of arachidonic acid by cyclooxygenases and PGD₂ synthases. PGD₂ is produced by mast cells, macrophages and T_(H)2 lymphocytes in response to local tissue damage as well as in response allergic inflammation observed in diseases such as asthma, rhinitis, and atopic dermatitis. Exogenous PGD₂ applied to bronchial airways elicits many responses that are characteristic of acute asthma.

Activation of DP₂ is associated with chemotaxis and activation of T_(H)2 lymphocytes, eosinophils and basophils. PGD₂ binds to DP₂ and mediates many of its effects through a G_(i)-dependent elevation of intracellular calcium levels and reduction of cyclic AMP. In T_(H)2 lymphocytes, IL4, IL5 and IL13 cytokine production are also stimulated by DP₂ activation. These cytokines have been implicated in numerous biological actions including, by way of example only, immunoglobulin E production, airway response, mucous secretion, and eosinophil recruitment.

In the brain and central nervous system, PGD₂ is produced and thought to function in pain perception and sleep regulation. In other tissues, PGD₂ is produced primarily in immunoglobulin E (IgE) activated mast cells and to a lesser extent, in macrophages, dendritic cells, T helper 2 (T_(H)2) lymphocytes and other leukocytes. In the cell, PGD₂ is rapidly metabolized and converted to other downstream effectors including Δ¹²PGJ₂, 9α11βPGF₂, 13,14-dihydro-15-keto-PGD₂, and 15-deoxy-Δ^(12,14)PGD₂.

Mast-cell-derived PGD₂ is produced in high concentrations in response to an allergen challenge. Studies in preclinical species have observed the following features when PGD₂ is applied to in vivo preparations, or its overproduction is engineered by genetic manipulation:

Vasodilatation leading to erythema (flare) and -potentiation of oedema (wheal).

Recruitment of eosinophils and TH2 lymphocytes.

Modulation of TH2-cytokine production.

Bronchoconstriction.

Injection of PGD₂ into human skin has been shown to produce a long lasting erythema, to potentiate the effects of other mediators on induration and leukocyte infiltration in human skin and to enhance oedema formation in rat skin. It is most likely that these effects of PGD₂, like those of other vasodilator prostaglandins, are due to an increased blood flow to the inflamed lesion and are, therefore, most likely to be mediated predominantly by the DP₁ receptor. Although these observations make it clear that DP₁ mediates the vascular effects of PGD₂, the capacity of PGD₂ to promote the cellular changes associated with inflammation is not due to an action on DP₁.

Much of PGD₂'s pro-inflammatory activity is through interaction with DP₂. DP₂ is a G-protein coupled receptor and is typically highly expressed in T_(H)2 lymphocytes, eosinophils and basophils. DP₂ activation functions to directly activate and recruit T_(H)2 lymphocytes and eosinophils. Activated T_(H)2 lymphocytes produce and secrete inflammatory cytokines including IL4, IL5, and IL13. Despite binding PGD₂ with a similar affinity as DP₁, DP₂ is not structurally related to DP₁ and signals through a different mechanism—the effects of DP₂ are mediated through Gi-dependent elevation in intracellular calcium levels and reduction in intracellular levels of cyclic AMP. DP₂ activation is important in eosinophil recruitment in response to allergic challenge in such tissues as nasal mucosa, bronchial airways, and skin. The application of either PGD₂ or selective DP₂ agonists both exacerbate and enhance allergic responses in lung and skin. DP₂ activation appears to have a crucial role in mediating allergic responses. The use of antagonists of PGD₂ activation of the DP₂ receptor is an approach to treat the inflammatory component of inflammatory diseases or conditions, respiratory diseases or conditions, allergic diseases or conditions, such as asthma, rhinitis, and dermatitis, among others.

Compounds

Compounds of Formula (I) have the following structure:

wherein,

-   -   R⁴ is selected from H, halogen, —CN, —OH, C₁-C₄alkyl,         C₁-C₄alkoxy, C₁-C₄fluoroalkyl, C₁-C₄fluoroalkoxy, and         C₁-C₄heteroalkyl;     -   R⁵ is H, halogen, —CN, —NO₂, —OH, —S(═O)₂R¹², —NHS(═O)₂R¹²,         —C(═O)R¹², —OC(═O)R¹², —CO₂R¹³, —N(R¹³)₂, —C(═O)N(R¹³)₂,         —NHC(═O)R¹², —C(OH)(R¹³)₂, C₁-C₄alkyl, C₁-C₄fluoroalkyl,         C₁-C₄fluoroalkoxy, C₁-C₄alkoxy, C₁-C₄heteroalkyl or —SR¹²;     -   R²⁰ is C₁-C₄alkyl, C₃-C₆cycloalkyl, —CH₂O—C₁-C₄alkyl,         —CH₂O-(substituted or unsubstituted phenyl),         —CH(CH₃)—O-(substituted or unsubstituted phenyl),         —C(CH₃)₂—O-(substituted or unsubstituted phenyl),         —CH₂OCH₂-(substituted or unsubstituted phenyl), —OC₁-C₄alkyl,         —O—CH₂-(substituted or unsubstituted phenyl),         —O—CH(CH₃)-(substituted or unsubstituted phenyl),         —NR¹⁶C₁-C₄alkyl, —NR¹⁶—CH₂-(substituted or unsubstituted         phenyl), or —NR¹⁶—CH(CH₃)-(substituted or unsubstituted phenyl),         wherein if the phenyl of R²⁰ is substituted, then the phenyl is         substituted with 0, 1, or 2 R²¹ groups;         -   R²¹ is selected from halogen, —OH, —OCH₃, C₁-C₄alkyl, and             —CF₃;         -   R¹⁶ is H or C₁-C₄alkyl;     -   R¹¹ is C₁-C₄alkyl, C₁-C₄fluoroalkyl, or C₃-C₆cycloalkyl;     -   R¹² is C₁-C₄alkyl, C₁-C₄heteroalkyl, or C₁-C₄fluoroalkyl;     -   each R¹³ is independently selected from H, C₁-C₄alkyl,         C₁-C₄heteroalkyl, and C₁-C₄fluoroalkyl.

In one aspect, the compound of Formula (I) has the following structure:

For any and all of the embodiments, substituents can be selected from among from a subset of the listed alternatives.

For example, in some embodiments, R¹¹ is —CH₃, —CH₂CH₃, —CF₃, —CH₂CF₃, cyclopropyl, cyclobutyl, or cyclopentyl. In other embodiments, R¹¹ is —CH₃, —CH₂CH₃, —CF₃, or —CH₂CF₃. In other embodiments, R¹¹ is —CH₃, —CH₂CH₃, or —CH₂CF₃. In yet other embodiments, R¹¹ is cyclopropyl, cyclobutyl, or cyclopentyl. In some embodiments, R¹¹ is —CH₃, or —CH₂CH₃. In yet other embodiments, R¹¹ is —CH₂CH₃.

In some embodiments, R⁴ is H, F, Cl, Br, —OH, —CH₃, —OCH₃, —CF₃, or —OCF₃. In some other embodiments, R⁴ is —OCH₃.

In some embodiments, R⁵ is H, halogen, —CN, —NO₂, —OH, —S(═O)₂CH₃, —NHS(═O)₂CH₃, —C(═O)CH₃, —OC(═O)CH₃, —CO₂H, —CO₂CH₃, —CO₂CH₂CH₃, —NH₂, —C(═O)NH₂, —NHC(═O)CH₃, —CH₃, —CF₃, —OCF₃, —OCH₃, —CH₂OH, or —C(CH₃)₂OH. In some other embodiments, R⁵ is H, F, Cl, Br, —CH₃, —CF₃, —OCF₃, or —OCH₃. In some other embodiments, R⁵ is —CH₃ or —CF₃. In some embodiments, R⁵ is —CF₃.

In some embodiments, R²⁰ is C₁-C₄alkyl, C₃-C₆cycloalkyl, —CH₂O—C₁-C₄alkyl, —CH₂O-phenyl, —CH(CH₃)—O-phenyl, —C(CH₃)₂—O-phenyl, —CH₂OCH₂-phenyl, —OC₁-C₄alkyl, —O—CH₂-phenyl, —O—CH(CH₃)-phenyl, —NR¹⁶C₁-C₄alkyl, —NR¹⁶—CH₂-phenyl, or —NR¹⁶—CH(CH₃)-phenyl. In one aspect, the phenyl group of R²⁰ is substituted with one or two R²¹ groups.

In some embodiments, R²⁰ is —CH₃, —CH₂CH₃, —CH(CH₃)₂, —C(CH₃)₃, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, —CH₂OCH₃, —CH₂O-(substituted or unsubstituted phenyl), —CH(CH₃)—O-(substituted or unsubstituted phenyl), —C(CH₃)₂—O-(substituted or unsubstituted phenyl), —CH₂OCH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.

In some embodiments, R²⁰ is —CH₃, —CH₂CH₃, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, —CH₂OCH₃, —CH₂O-(substituted or unsubstituted phenyl), —CH(CH₃)—O-(substituted or unsubstituted phenyl), —C(CH₃)₂—O-(substituted or unsubstituted phenyl), —CH₂OCH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.

In other embodiments, R²⁰ is —CH₃, cyclopropyl, —CH₂OCH₃, —CH₂O-(substituted or unsubstituted phenyl), —CH₂OCH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.

In other embodiments, R²⁰ is C₁-C₄alkyl, C₃-C₆cycloalkyl, or —CH₂O—C₁-C₄alkyl. In other embodiments, R²⁰ is C₁-C₄alkyl. In other embodiments, R²⁰ is —CH₃. In some other embodiments, R²⁰ is C₃-C₆cycloalkyl. In other embodiments, R²⁰ is cyclopropyl.

In some embodiments, R²⁰ is —CH₂O—C₁-C₄alkyl, —CH₂O-(substituted or unsubstituted phenyl), —CH(CH₃)—O-(substituted or unsubstituted phenyl), —C(CH₃)₂—O-(substituted or unsubstituted phenyl), or —CH₂OCH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups.

In yet other embodiments, R²⁰ is —OC₁—C₄alkyl, —O—CH₂-(substituted or unsubstituted phenyl), or —O—CH(CH₃)-(substituted or unsubstituted phenyl); wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.

In yet other embodiments, R²⁰ is —OC₁-C₄alkyl. In some embodiments, R²⁰ is —O—CH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups.

In some embodiments, each R²¹ is independently selected from F, Cl, and Br.

In one aspect, the compound of Formula (I) has the following structure:

wherein, n is 0, 1, or 2;

In one aspect, R⁴ is F, Cl, Br, —CH₃, —OCH₃, —CF₃, or —OCF₃. In one aspect, R⁵ is F, Cl, Br, —CH₃, —CF₃, —OCF₃, or —OCH₃. In one aspect, R¹¹ is —CH₃, —CH₂CH₃, or —CH₂CF₃.

In one aspect, n is 0. In another aspect, n is 1. In yet another aspect, n is 2.

In some embodiments, R²⁰ is —NR¹⁶C₁-C₄alkyl, —NR¹⁶—CH₂-(substituted or unsubstituted phenyl), or —NR¹⁶—CH(CH₃)-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃; R¹⁶ is H, —CH₃, or —CH₂CH₃.

In some embodiments, R¹⁶ is H, —CH₃, or —CH₂CH₃. In other embodiments, R¹⁶ is H.

In some embodiments, R²⁰ is —NR¹⁶C₁-C₄alkyl.

In some embodiments, R²⁰ is —NR¹⁶—CH₂-(substituted or unsubstituted phenyl), or —NR¹⁶—CH(CH₃)-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups.

In some embodiments, R²⁰ is —NH—CH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups.

In some embodiments, each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃. In other embodiments, each R²¹ is independently selected from F, Cl, and Br.

In one aspect, the compound of Formula (I) has the following structure:

wherein, n is 0, 1, or 2.

each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.

In one aspect, R⁴ is F, Cl, Br, —CH₃, —OCH₃, —CF₃, or —OCF₃. In one aspect, R⁵ is F, Cl, Br, —CH₃, —CF₃, —OCF₃, or —OCH₃.

In one aspect, R¹¹ is —CH₃, —CH₂CH₃, or —CH₂CF₃.

In some embodiments, wherein, n is 0, 1, or 2; R⁴ is —OCH₃; R⁵ is —CF₃; R¹¹ is —CH₃, or —CH₂CH₃; each R²¹ is independently selected from F, Cl, and Br.

In one aspect, n is 0. In another aspect, n is 1. In yet another aspect, n is 2.

In one aspect, R⁴ is —OCH₃. In one aspect, R⁵ is —CF₃. In one aspect, R¹¹ is —CH₃, or —CH₂CH₃. In one aspect, R¹¹ is —CH₂CH₃.

In one aspect, R¹² is C₁-C₄alkyl or C₁-C₄fluoroalkyl. In one aspect, R¹² is C₁-C₄alkyl.

In one aspect, each R¹³ is independently selected from H, C₁-C₄alkyl, and C₁-C₄fluoroalkyl. In one aspect, each R¹³ is independently selected from H and C₁-C₄alkyl.

In one aspect, R⁴ is as defined in Table 1. In one aspect, R⁵ is as defined in Table 1. In one aspect, R²⁰ is as defined in Table 1. In one aspect, R¹¹ is as defined in Table 1.

Any combination of the groups described above for the various variables is contemplated herein. Throughout the specification, groups and substituents thereof are chosen by one skilled in the field to provide stable moieties and compounds.

In one aspect, compounds of Formula (I) include, but are not limited to, those described in Table 1:

TABLE 1

Cmpd # R⁴ R⁵ R¹¹ R²⁰ M + H 1-1 OCH₃ CF₃ CH₃ —CH₃ 396 1-2 OCH₃ CF₃ CH₂CH₃ —CH₃ 410 1-3 OCH₃ CF₃ CH₂C(CH₃)₃ —CH₃ 452 1-4 OCH₃ CF₃ CH₂CF₃ —CH₃ 464 1-10 F CF₃ CH₂CH₃ —CH₃ 398 1-11 F CF₃ CH₂CF₃ —CH₃ 452 1-12 OCH₃ CF₃ Cyclopropyl —CH₃ 422 1-23 OCH₃ CF₃ CH₂CH₃ —OCH₃ 426 1-27 OCH₃ CF₃ CH₃ —OCH₂Ph 488 1-28 OCH₃ CF₃ CH₂CH₃ —OCH₂Ph 502 1-29 F CF₃ CH₃ —OCH₂Ph 476 1-30 OCH₃ CF₃ Cyclobutyl —CH₃ 436 1-31 OCH₃ CF₃ Cyclopentyl —CH₃ 450 1-32 OCH₃ CF₃ CH₂CH₃ —CF₃ 464 1-33 OCH₃ CF₃ CH₂CH₃ -(cyclopropyl) 436 1-34 OCH₃ CF₃ Cyclobutyl —OCH₂Ph 528 1-35 OCH₃ CF₃ Cyclopentyl —OCH₂Ph 542 1-36 OCH₃ CF₃ Cyclopropyl —OCH₂Ph 514 1-37 OCH₃ CO₂H CH₂CF₃ —CH₃ 440 1-38 OCH₃ CF₃ CH₂CH₃ —OCH₂-(3,5-dichlorophenyl) 571 1-39 OCH₃ CF₃ CH₂CH₃ —OCH₂-(2-chlorophenyl) 536 1-40 OCH₃ CF₃ CH₂CH₃ —OCH₂-(3,5-difluorophenyl) 538 1-41 OCH₃ CF₃ CH₂CH₃ —OCH₂-(4-fluorophenyl) 520 1-42 OCH₃ CF₃ CH₂CH₃ —OCH₂-(4-chlorophenyl) 536 1-43 OCH₃ CF₃ CH₂CH₃ —OCH₂-(3-chlorophenyl) 536 1-44 OCH₃ CF₃ CH₂CH₃ —O—CH(CH₃)(4-chlorophenyl) 550 1-45 OCH₃ CF₃ CH₂CH₃ —CH(CH₃)(OPh) 516 1-46 OCH₃ CF₃ CH₂CH₃ —CH₂OCH₃ 440 1-48 OCH₃ CF₃ CH₂CH₃ —CH₂OPh 502 1-49 F CF₃ CH₂CF₃ —OCH₂Ph 544 1-50 OCH₃ Br CH₂CH₃ —CH₃ 1-51 OCH₃ NH—C(═O)—CH₃ CH₂CH₃ —CH₃ 1-56 CH₃ CF₃ CH₂CH₃ —CH₃ 1-58 F CF₃ CH₃ —CH₃ 1-59 CH₃ CF₃ CH₃ —CH₃ 1-60 Cyclo-propyl CF₃ CH₂CH₃ —CH₃ 1-61 CF₃ CF₃ CH₂CH₃ —CH₃ 1-63 OCH₃ Br CH₃ —CH₃ 1-64 OCH₃ NH—C(═O)—CH₃ CH₃ —CH₃ 1-65 OCH₃ NH—C(═O)—OCH₃ CH₂CH₃ —CH₃ 1-66 OCH₃ NH—SO₂CH₃ CH₂CH₃ —CH₃ 1-67 OCH₃ SO₂CH₃ CH₂CH₃ —CH₃ 1-75 OCH₃ CF₃ CH₂CH₃ —O-(cyclopropyl) 1-76 OCH₃ CF₃ CH₂CH₃ —NHCH₃ 1-77 OCH₃ CF₃ CH₃ -(cyclopropyl) 1-78 OCH₃ CF₃ CH₂CH₃ -(cyclopentyl) 1-79 Cl CF₃ CH₂CH₃ —CH₃ 1-92 OCH₃ CF₃ CH₂CH₃ —CH₂OCH₂Ph 1-93 OCH₃ CF₃ CH₂CH₃ —CH₂O-(4-chlorophenyl) 1-94 OCH₃ CF₃ CH₂CH₃ —N(CH₂CH₃)(CH₂Ph) 1-96 OCH₃ CF₃ CH₂CH₃ —NHCH₂Ph 501 1-110 Cl CF₃ CH₂CH₃ —OCH₂Ph 506 1-118 OCH₃ CF₃ CH₂CH₃ —C(CH₃)₂—O-(4-chlorophenyl) 565 1-128 OCH₂-Ph CF₃ CH₂CH₃ —OCH₂Ph 578 1-129 OCH₂—CH₃ CF₃ CH₂CH₃ —OCH₂Ph 516 1-130 OCH₂-(cyclo- CF₃ CH₂CH₃ —OCH₂Ph 542 propyl) 1-143 H CF₃ CH₂CH₃ —OCH₂Ph 472 1-152 OCH₃ CF₃ CH₂CH₃ —NHCH₂-(3,4-dichlorophenyl) 569 1-153 OCH₃ NH—(C═O)—CH₃ CH₂CH₃ —OCH₂Ph 1-155 OCH₃ NH—SO₂—CH₃ CH₂CH₃ —OCH₂Ph 1-165 OCH₃ CF₃ CH₂CH₃ —NHCH₂-(3,5-dichlorophenyl) 570 1-176 OCH₃ CF₃ CH₂CH₃ —NHCH₂-(4-fluorophenyl) 519 1-177 OCH₃ CF₃ CH₂CH₃ —NHCH₂-(3-chlorophenyl) 535 1-178 OCH₃ CF₃ CH₂CH₃ —NHCH₂-(3,5-difluorophenyl) 537 1-179 OCH₃ CF₃ CH₂CH₃ (R)—NH—CH(CH₃)(4-chlorophenyl) 549 1-180 OCH₃ CF₃ CH₂CH₃ (S)—NH—CH(CH₃)(4-chlorophenyl) 549 1-181 OCH₃ CF₃ CH₂CH₃ —NHCH₂CH₃ 439 1-182 OCH₃ CF₃ CH₂CH₃ —NH-(cyclopropyl) 451 1-183 OCH₃ F CH₂CH₃ —OCH₂Ph 452 1-184 OCH₃ F CH₂CH₃ —CH₃ 360 1-185 OCH₃ F CH₂CH₃ —NHCH₂-(4-chlorophenyl) 486 1-186 OCH₃ F CH₂CH₃ -(cyclopropyl) 386 1-187 OCH₃ F CH₂CH₃ —NHCH₂Ph 451 1-206 OCH₃ CF₃ CH₂CH₃ -(cyclobutyl) 450 1-215 OCH₃ SO₂——CH₃ CH₂CH₃ —OCH₂Ph 512 1-216 OCH₃ C(CH₃)₂—(OH) CH₂CH₃ —OCH₂Ph 492 1-220 OH CF₃ CH₂CH₃ —NHCH₂Ph 487 1-226 OCH₃ COOH CH₂CH₃ —OCH₂Ph 478 1-241 OCH₃ SCH₃ CH₂CH₃ -(cyclopropyl) 414 1-244 H CF₃ CH₂CH₃ -(cyclopropyl) 406 1-245 OCH₃ CF₃ CH₂CH₃ —C(CH₃)₃ 452 1-246 OCH₃ CF₃ CH₂CH₃ —CH(CH₃)₂ 438 1-247 OCH₃ Br CH₂CH₃ -(cyclopropyl) 446 1-252 OCH₃ CF₃ CH₂CH₃ —NHCH₂-(4-hydroxyphenyl) 517 1-253 OCH₃ CF₃ CH₂CH₃ —NHCH₂-(2-hydroxyphenyl) 517 1-257 OCH₃ CF₃ CH₂CH₃ —NHCH₂-(3-hydroxyphenyl) 517 M + H refers to mass spectrometric data, where M represents the molecular ion peak.

Further Forms of Compounds

In certain embodiments, compounds of Formula (I) are prepared as pharmaceutically acceptable salts by reacting the free base form of the compound with a pharmaceutically acceptable inorganic or organic acid, including, but not limited to, inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid metaphosphoric acid, and the like; and organic acids such as acetic acid, propionic acid, hexanoic acid, cyclopentanepropionic acid, glycolic acid, pyruvic acid, lactic acid, malonic acid, succinic acid, malic acid, maleic acid, fumaric acid, p-toluenesulfonic acid, tartaric acid, trifluoroacetic acid, citric acid, benzoic acid, 3-(4-hydroxybenzoyl)benzoic acid, cinnamic acid, mandelic acid, arylsulfonic acid, methanesulfonic acid, ethanesulfonic acid, 1,2-ethanedisulfonic acid, 2-hydroxyethanesulfonic acid, benzenesulfonic acid, 2-naphthalenesulfonic acid, 4-methylbicyclo-[2.2.2]oct-2-ene-1-carboxylic acid, glucoheptonic acid, 4,4′-methylenebis-(3-hydroxy-2-ene-1-carboxylic acid), 3-phenylpropionic acid, trimethylacetic acid, tertiary butylacetic acid, lauryl sulfuric acid, gluconic acid, glutamic acid, hydroxynaphthoic acid, salicylic acid, stearic acid, and muconic acid.

Pharmaceutically acceptable salts are also obtained by reacting a compound of Formula (I) with a base to form a salt such as an ammonium salt, an alkali metal salt, such as a sodium or a potassium salt, an alkaline earth metal salt, such as a calcium or a magnesium salt, a salt of organic bases such as dicyclohexylamine, N-methyl-D-glucamine, tris(hydroxymethyl)methylamine, and salts with amino acids such as arginine, lysine, and the like.

In other embodiments, compounds of Formula (I) are prepared as a pharmaceutically acceptable salts by reacting the free acid form of the compound with a pharmaceutically acceptable inorganic or organic base, including, but not limited to organic bases such as ethanolamine, diethanolamine, triethanolamine, tromethamine, N-methylglucamine, and the like, or with an inorganic base such as aluminum hydroxide, calcium hydroxide, potassium hydroxide, sodium carbonate, sodium hydroxide, and the like.

Reference to a pharmaceutically acceptable salt includes the solvent addition forms or crystal forms thereof, particularly solvates or polymorphs. Solvates contain either stoichiometric or non-stoichiometric amounts of a solvent, and are optionally formed during the process of crystallization with pharmaceutically acceptable solvents such as water, ethanol, and the like. Hydrates are formed when the solvent is water, and alcoholates are formed when the solvent is alcohol. Solvates of compounds of Formula (I) are conveniently prepared or formed during the processes described herein. By way of example only, hydrates of compounds of Formula (I) are conveniently prepared by recrystallization from an aqueous/organic solvent mixture, using organic solvents including, but not limited to, dioxane, tetrahydrofuran, ethanol, or methanol. In addition, the compounds provided herein can exist in unsolvated as well as solvated forms. In general, the solvated forms are considered equivalent to the unsolvated forms for the purposes of the compounds and methods provided herein.

In some embodiments, compounds of Formula (I) are prepared as prodrugs. A “prodrug” refers to an agent that is converted into the parent drug in vivo.

In yet another embodiment, the compounds of Formula (I) possess one or more stereocenters and each center exists independently in either the R or S configuration. The compounds presented herein include all diastereomeric, enantiomeric, and epimeric forms as well as the appropriate mixtures thereof. Stereoisomers are obtained, if desired, by methods such as, the separation of stereoisomers by chiral chromatographic columns or stereoselective synthesis.

The methods and formulations described herein include the use of N-oxides (if appropriate), crystalline forms (also known as polymorphs), or pharmaceutically acceptable salts of compounds having the structure of Formula (I), as well as active metabolites of these compounds having the same type of activity. In some situations, compounds exist as tautomers.

In some embodiments, the compounds described herein exist as tautomers. All tautomers are intended to be within the scope of the molecular formulas described herein.

DEFINITIONS

Unless otherwise stated, the following terms used in this application, including the specification and claims, have the definitions given below. It must be noted that, as used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. In this application, the use of “or” or “and” means “and/or” unless stated otherwise. Furthermore, use of the term “including” as well as other forms, such as “include”, “includes,” and “included,” is not limiting.

“Alkoxy” refers to (alkyl)O—, where alkyl is as defined herein.

“Alkyl” refers to an aliphatic hydrocarbon group. The alkyl may be saturated or unsaturated. In one aspect, alkyl groups are selected from methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, and t-butyl.

“Cycloalkyl” refers to a monocyclic aliphatic, non-aromatic radical, wherein each of the atoms forming the ring (i.e. skeletal atoms) is a carbon atom. In some embodiments, cycloalkyl groups are selected from among cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl.

“Halo”, “halogen” or “halide” means fluoro, chloro, bromo or iodo.

“Fluoroalkyl” refers to an alkyl in which one or more hydrogen atoms are replaced by a fluorine atom. In one aspect, a fluoroalkyl is selected from —CF₃, —CHF₂, —CH₂F, —CH₂CF₃ and —CF₂CF₃.

“Fluoroalkoxy” refers to (fluoroalkyl)O—, where fluoroalkyl is as defined herein.

“Heteroalkyl” refers to an alkyl group in which one or more skeletal atoms of the alkyl are selected from an atom other than carbon, e.g., oxygen, nitrogen, sulfur, phosphorus or combinations thereof. In one aspect, heteroalkyl refers to an alkyl group in which one of the skeletal atoms of the alkyl is oxygen, nitrogen, or sulfur. In another aspect, heteroalkyl refers to an alkyl group in which one of the skeletal atoms of the alkyl is oxygen.

The term “optionally substituted” or “substituted” means that the referenced group may be substituted with one or more additional group(s) individually and independently selected from halogen, —OH, —CN, C₁-C₄alkyl, C₁-C₄fluoroalkyl, C₁-C₄alkoxy, C₁-C₄fluoroalkoxy, and C₁-C₄heteroalkyl.

A “metabolite” of a compound disclosed herein is a derivative of that compound that is formed when the compound is metabolized. The term “active metabolite” refers to a biologically active derivative of a compound that is formed when the compound is metabolized.

“PGD₂-dependent” refers to conditions or disorders that would not occur, or would not occur to the same extent, in the absence of PGD₂. “PGD₂-mediated” refers to refers to conditions or disorders that might occur in the absence of PGD₂ but can occur in the presence of PGD₂.

“Effective amount” or “therapeutically effective amount,” as used herein, refer to a sufficient amount of an agent or a compound being administered which will relieve to some extent one or more of the symptoms of the disease or condition being treated. An appropriate effective amount in any individual case may be determined using techniques, such as a dose escalation study.

The terms “treat,” “treating” or “treatment,” as used herein, include alleviating, abating or ameliorating a disease or condition symptoms, preventing additional symptoms, ameliorating or preventing the underlying metabolic causes of symptoms, inhibiting the disease or condition, e.g., arresting the development of the disease or condition, relieving the disease or condition, causing regression of the disease or condition, relieving a condition caused by the disease or condition, or stopping the symptoms of the disease or condition either prophylactically and/or therapeutically.

The term “subject” or “patient” encompasses mammals and non-mammals. In one aspect, the “subject” or “patient” is a mammal. In one embodiment, the mammal is a human.

Pharmaceutical Composition/Formulation

Suitable routes of administration include, but are not limited to, oral, intravenous, rectal, aerosol, parenteral, ophthalmic, pulmonary, transmucosal, transdermal, vaginal, otic, nasal, intramuscular injection, subcutaneous injection, and topical administration. In addition, by way of example only, parenteral delivery includes intramuscular, subcutaneous, intravenous, intramedullary injections, as well as intrathecal, direct intraventricular, intraperitoneal, intralymphatic, and intranasal injections.

In certain embodiments, a compound as described herein is administered in a local rather than systemic manner. In other embodiments, the compound as described herein is provided in the form of a rapid release formulation, in the form of an extended release formulation, or in the form of an intermediate release formulation. In yet other embodiments, the compound described herein is administered topically.

In some embodiments, the compounds described herein are formulated into pharmaceutical compositions. In specific embodiments, pharmaceutical compositions are formulated in a conventional manner using one or more physiologically acceptable carriers comprising excipients and auxiliaries which facilitate processing of the active compounds into preparations which can be used pharmaceutically. Proper formulation is dependent upon the route of administration chosen. Any pharmaceutically acceptable techniques, carriers, and excipients are used as suitable to formulate the pharmaceutical compositions described herein: Remington: The Science and Practice of Pharmacy, Nineteenth Ed (Easton, Pa.: Mack Publishing Company, 1995); Hoover, John E., Remington's Pharmaceutical Sciences, Mack Publishing Co., Easton, Pa. 1975; Liberman, H. A. and Lachman, L., Eds., Pharmaceutical Dosage Forms, Marcel Decker, New York, N.Y., 1980; and Pharmaceutical Dosage Forms and Drug Delivery Systems, Seventh Ed. (Lippincott Williams & Wilkins 1999).

A pharmaceutical composition refers to a mixture of a compound of Formula (I) with other chemical components, such as carriers, stabilizers, diluents, dispersing agents, suspending agents, thickening agents, and/or excipients. In certain embodiments, the pharmaceutical composition facilitates administration of the compound to a mammal.

In one embodiment, compounds of Formula (I) are formulated in an aqueous solution. In specific embodiments, the aqueous solution is selected from, by way of example only, a physiologically compatible buffer, such as Hank's solution, Ringer's solution, or physiological saline buffer. In other embodiments, compounds of Formula (I) are formulated for transmucosal administration. In specific embodiments, transmucosal formulations include penetrants that are appropriate to the barrier to be permeated. In still other embodiments wherein the compounds described herein are formulated for other parenteral injections, appropriate formulations include aqueous or nonaqueous solutions.

In another embodiment, compounds described herein are formulated for oral administration. The compounds described herein are formulated in oral dosage forms that include, by way of example only, tablets, powders, pills, dragees, capsules, liquids, gels, syrups, elixirs, slurries, suspensions and the like.

In certain embodiments, pharmaceutical preparations for oral use are obtained by mixing one or more solid excipient with one or more of the compounds described herein, optionally grinding the resulting mixture, and processing the mixture of granules, after adding suitable auxiliaries, if desired, to obtain tablets or pills. Suitable excipients are, in particular, fillers such as sugars, including lactose, sucrose, mannitol, or sorbitol; cellulose preparations such as: for example, maize starch, wheat starch, rice starch, potato starch, gelatin, gum tragacanth, methylcellulose, microcrystalline cellulose, hydroxypropylmethylcellulose, sodium carboxymethylcellulose; or others such as: polyvinylpyrrolidone (PVP or povidone) or calcium phosphate. In specific embodiments, disintegrating agents are optionally added. Disintegrating agents include, by way of example only, cross-linked croscarmellose sodium, polyvinylpyrrolidone, agar, or alginic acid or a salt thereof such as sodium alginate.

Oral dosage forms also include push-fit capsules made of gelatin, as well as soft, sealed capsules made of gelatin and a plasticizer, such as glycerol or sorbitol. In specific embodiments, push-fit capsules contain the active ingredients in admixture with one or more filler. Fillers include, by way of example only, lactose, binders such as starches, and/or lubricants such as talc or magnesium stearate and, optionally, stabilizers. In other embodiments, soft capsules contain one or more active compound that is dissolved or suspended in a suitable liquid. Suitable liquids include, by way of example only, one or more fatty oil, liquid paraffin, or liquid polyethylene glycol. In addition, stabilizers are optionally added.

In still other embodiments, the compounds of Formula (I) are administered topically. Topically administrable compositions include solutions, suspensions, lotions, gels, pastes, medicated sticks, balms, creams or ointments.

In other embodiments, the compounds of Formula (I) are formulated for administration by inhalation. Various forms suitable for administration by inhalation include, but are not limited to, aerosols, mists or powders.

The active ingredient in the pharmaceutical compositions is in free-acid or free-base form, or in a pharmaceutically acceptable salt form. In addition, the methods and pharmaceutical compositions described herein include the use of N-oxides, crystalline forms (also known as polymorphs), as well as active metabolites of these compounds having the same type of activity. All tautomers of the compounds described herein are included within the scope of the compounds presented herein. Additionally, the compounds described herein encompass unsolvated as well as solvated forms with pharmaceutically acceptable solvents such as water, ethanol, and the like. The solvated forms of the compounds presented herein are also considered to be disclosed herein. In addition, the pharmaceutical compositions optionally include other medicinal or pharmaceutical agents, carriers, adjuvants, such as preserving, stabilizing, wetting or emulsifying agents, solution promoters, salts for regulating the osmotic pressure, buffers, and/or other therapeutically valuable substances.

In certain embodiments, the compositions containing the compound(s) described herein are administered for prophylactic and/or therapeutic treatments. In certain therapeutic applications, the compositions are administered to a patient already suffering from a disease or condition, in an amount sufficient to cure or at least partially arrest the symptoms of the disease or condition. Amounts effective for this use depend on the severity and course of the disease or condition, previous therapy, the patient's health status, weight, and response to the drugs, and the judgment of the treating physician. Therapeutically effective amounts are optionally determined by methods including, but not limited to, a dose escalation clinical trial.

In prophylactic applications, compositions comprising the compounds described herein are administered to a patient susceptible to or otherwise at risk of a particular disease, disorder or condition. In this use, the precise amounts also depend on the patient's state of health, weight, and the like.

The amount of a given agent that corresponds to such an amount varies depending upon factors such as the particular compound, disease or condition and its severity, the identity (e.g., weight) of the mammal in need of treatment, but can nevertheless be determined according to the particular circumstances surrounding the case, including, e.g., the specific agent being administered, the route of administration, the condition being treated, and the mammal being treated. Doses employed for adult human treatment are typically in the range of 0.02-5000 mg per day, 1-1500 mg per day, 1-500 mg per day or 1-100 mg per day. In one embodiment, the dose is presented in a single dose or in divided doses administered at appropriate intervals, for example as two, three, four or more sub-doses per day.

In one embodiment, the daily dosages appropriate for the compound of Formula (I) are from about 0.01 to about 10 mg/kg per body weight. In certain embodiments, suitable unit dosage forms for oral administration comprise from about 1 to 500 mg active ingredient. In other embodiments, the daily dosage or the amount of active in the dosage form are lower or higher than the ranges indicated herein.

In one aspect, compounds of Formula (I) are used in the treatment of PGD₂-dependent or PGD₂-mediated diseases, disorders or conditions as disclosed herein. In one aspect, compounds of Formula (I) are DP₂ antagonists. In one aspect, the compounds of Formula (I) exhibit negligible modulatory activity on CETP and/or PPAR receptors. CETP assays are known (Epps et al. Chem. Phys. Lipids. 77, 51-63, 1995). PPAR assays are known (Example 48 of US 2006/0058301).

In certain instances, it is appropriate to administer at least one compound of Formula (I) in combination with another therapeutic agent. In combination therapies, the multiple therapeutic agents (one of which is one of the compounds described herein) are administered in any order or even simultaneously. If administration is simultaneous, the multiple therapeutic agents are, by way of example only, provided in a single, unified form, or in multiple forms (e.g., as a single pill or as two separate pills).

EXAMPLES

These examples are provided for illustrative purposes only and not to limit the scope of the claims provided herein.

Example 1 Synthesis of {2′-[(Acetyl-methyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-1) Step 1: (3-Bromo-4-methoxy-phenyl)-acetic acid methyl ester

To (3-bromo-4-methoxy-phenyl)-acetic acid (5.226 g, 21.32 mmol) in MeOH (52 mL) was added thionyl chloride (3.1 mL, 42.65 mmol), and the reaction was stirred at room temperature for 2 hours. Once no starting material was seen by analytical LCMS, the mixture was concentrated and then diluted with CH₂Cl₂ and aqueous 1N NaOH. The aqueous layer was separated and extracted with CH₂Cl₂, and the combined organic layers were washed with H₂O, dried over MgSO₄, filtered, and concentrated to give the title compound.

Step 2: [4-Methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid methyl ester

(3-Bromo-4-methoxy-phenyl)-acetic acid methyl ester (5.1 g, 19.68 mmol), bis(pinacolato)diboron (6.54 g, 25.59 mmol), and potassium acetate (5.80 g, 59.05 mmol) were combined in DMF (100 mL) under N₂. The solution was purged with N₂, and then (1,1′-bis(diphenylphosphino)ferrocene)-dichloropalladium(II) (0.805 g, 0.98 mmol) was added and the reaction was heated to 85° C. overnight. Starting material was still observed after 16 hours, so additional (1,1′-bis(diphenylphosphino)ferrocene)-dichloropalladium(II) (0.808 g, 0.98 mmol) was added, and the reaction was stirred at 85° C. overnight. Once no starting material was seen by analytical LCMS, the mixture was cooled to room temperature and concentrated. The residue was partitioned between EtOAc and H₂O and filtered through Celite. The aqueous layer was separated and extracted with EtOAc, and the combined organic layers were washed with brine, dried over MgSO₄, filtered, and concentrated. The residue was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give the title compound.

Step 3: 2-Bromo-5-trifluoromethyl-benzaldehyde

To (2-bromo-5-trifluoromethyl-phenyl)-methanol (2.216 g, 8.69 mmol) and N-methylmorpholine N-oxide (2.051 g, 17.38 mmol) in CH₂Cl₂ (44 mL) and MeCN (2.2 mL) was added tetrapropylammonium perruthenate (0.311 g, 0.87 mmol), and the reaction was stirred at room temperature for 20 minutes. Once no starting material was seen by analytical tlc, the mixture was concentrated and purified by silica gel chromatography to give the title compound.

Step 4: (2′-Formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

2-Bromo-5-trifluoromethyl-benzaldehyde (4.152 g, 16.41 mmol), [4-methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid methyl ester (4.988 g, 16.41 mmol), and potassium carbonate (5.67 g, 41.03 mmol) were combined in DME (40 mL) and H₂O (20 mL) under N₂. The mixture was purged with N₂, and then tetrakis(triphenylphosphine)palladium(0) (1.9 g, 1.64 mmol) was added, and the reaction was heated to 90° C. for 10 hours. Once no starting material was seen by analytical LCMS, the mixture was cooled to room temperature and diluted with CH₂Cl₂ and H₂O. The aqueous layer was separated and extracted with CH₂Cl₂, and the combined organic layers were dried over MgSO₄, filtered, and concentrated. The residue was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give the title compound.

Step 5: (6-Methoxy-2′-methylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

To (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.228 g, 0.65 mmol) and methylamine (2M in THF; 0.5 mL, 0.84 mmol) in CH₂Cl₂ (3.4 mL) was added sodium cyanoborohydride (0.061 g, 0.97 mmol), followed by acetic acid (1 drop). The reaction was stirred at room temperature overnight, until no starting material was seen by analytical LCMS. The solution was neutralized with saturated aqueous NaHCO₃ and extracted with CH₂Cl₂, and the combined organic layers were dried over MgSO₄, filtered, and concentrated to give the title compound.

Step 6: {2′-[(Acetyl-methyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester

To (6-methoxy-2′-methylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.114 g, 0.31 mmol) and triethylamine (0.05 mL, 0.34 mmol) in CH₂Cl₂ (1.2 mL) was added acetyl chloride (0.02 mL, 0.34 mmol), and the reaction was stirred at room temperature for 1 hour. Once no starting material was seen by analytical LCMS, the mixture was diluted with CH₂Cl₂ and H₂O, and the aqueous layer was extracted with CH₂Cl₂. The combined organic layers were dried over MgSO₄, filtered, and concentrated, and the residue was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give the title compound.

Step 7: {2′-[(Acetyl-methyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

{2′-[(Acetyl-methyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ester (0.038 g, 0.09 mmol) was dissolved in THF (0.38 mL), MeOH (0.3 mL), and aqueous 1N NaOH (0.2 mL), and the mixture was stirred at room temperature for 1 hour. Once no starting material was seen by analytical LCMS, the mixture was diluted with CH₂Cl₂ and H₂O, and the aqueous layer was extracted with CH₂Cl₂. The combined organic layers were dried over MgSO₄, filtered, and concentrated, and the residue was purified by preparative HPLC. The desired fractions were combined, concentrated, and the isolated material was diluted with CH₂Cl₂ and neutralized with saturated aqueous NaHCO₃. The organic layer was separated, dried over MgSO₄, filtered, and concentrated to give the title compound. The aqueous layer was acidified and extracted with EtOAc, and the organic layer was concentrated to give additional product.

{2′-[(Acetyl-cyclopropyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-12) was prepared following the procedures of Example 1 and using (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester, cyclopropylamine, and acetyl chloride.

{2′-[(Acetyl-cyclobutyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-30) was prepared according to the procedures outlined in Example 1 by using the following materials: (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester, cyclobutylamine and acetyl chloride.

{2′-[(Acetyl-cyclopentyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-31) was prepared according to the procedures outlined in Example 1 by using the following materials: (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester, cyclopentylamine and acetyl chloride.

{4′-Bromo-2′-[(cyclopropanecarbonyl-ethyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-247) was prepared by following the procedures of Example 1 using the following materials: (5-bromo-2-iodo-benzyl)-ethyl-amine, cyclopropanecarbonyl chloride, and [4-methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester.

{2′-[(Benzyloxycarbonyl-cyclobutyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-34) was prepared by following the procedures of Example 1 and using the following starting materials: (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester, cyclobutylamine, and benzyl chloroformate.

{2′-[(Benzyloxycarbonyl-cyclopentyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-35) was prepared by following the procedures of Example 1 and using the following starting materials: (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester, cyclopentylamine, and benzyl chloroformate.

{2′-[(Benzyloxycarbonyl-cyclopropyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-36) was prepared by following the procedures of Example 1 and using the following starting materials: (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester, cyclopropylamine, and benzyl chloroformate

Example 2 Synthesis of {2′-[(Acetyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-2) Step 1: (2′-Ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 5, using the following starting materials: (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and ethylamine (2M in THF).

Step 2: {2′-[(Acetyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 6, using the following starting materials: (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and acetyl chloride.

Step 3: {2′-[(Acetyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

Prepared according to the procedure described in Example 1, Step 7, using the following starting material: {2′-[(acetyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ester.

{2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-33) was prepared by following the procedures of Example 1 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and cyclopropanecarbonyl chloride.

(2′-{[Ethyl-(2-phenoxy-propionyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-45) was prepared by following the procedures outlined in Example 1 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and 2-phenoxypropionyl chloride.

(2′-{[Ethyl-(2-phenoxy-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-48) was prepared by following the procedures outlined in Example 1 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and phenoxyacetyl chloride.

(2′-{[(2-Benzyloxy-acetyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-92) was prepared by following the procedures outlined in Example 1 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and benzyloxyacetyl chloride.

[2′-({[2-(4-Chloro-phenoxy)-acetyl]-ethyl-amino}-methyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]acetic acid (Compound 1-93) was prepared by following the procedures outlined in Example 1 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and 4-chlorophenoxyacetyl chloride.

{2′-[(Cyclobutanecarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-206) was prepared using the procedures of Example 1 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester and cyclobutanecarbonyl chloride.

(2′-{[(2,2-Dimethyl-propionyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-245) was prepared using the procedures of Example 1 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester and trimethylacetyl chloride.

{2′-[(Ethyl-isobutyryl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-246) was prepared using the procedures of Example 1 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester and isobutyryl chloride.

Example 3 Synthesis of (2′-{[Acetyl-(2,2-dimethyl-propyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-3) Step 1: {2′-[(2,2-Dimethyl-propylamino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 5, using the following starting materials: (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and neopentylamine.

Step 2: (2′-{[Acetyl-(2,2-dimethyl-propyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 6, using the following starting materials: {2′-[(2,2-dimethyl-propylamino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester and acetyl chloride.

Step 3: (2′-{[Acetyl-(2,2-dimethyl-propyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid

(2′-{[Acetyl-(2,2-dimethyl-propyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-acetic acid methyl ester (0.152 g, 0.33 mmol) was dissolved in THF (1.5 mL), MeOH (1.2 mL), and aqueous 1N NaOH (0.72 mL), and the mixture was stirred at room temperature for 4 hours. Once no starting material was seen by analytical LCMS, the mixture was diluted with CH₂Cl₂ and aqueous 1N HCl, and the aqueous layer was extracted with CH₂Cl₂. The combined organic layers were dried over MgSO₄, filtered, and concentrated to give the title compound.

Example 4 Synthesis of (2′-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-4) Step 1: {6-Methoxy-2′-[(2,2,2-trifluoro-ethylamino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester

2,2,2-Trifluoroethylamine hydrochloride (0.101 g, 0.71 mmol) was treated with sodium acetate (0.061 g, 0.71 mmol) in MeOH (1 mL) with heating and sonication. (2′-Formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.207 g, 0.59 mmol) in MeOH (2 mL) was added, followed by sodium cyanoborohydride (0.069 g, 1.06 mmol), and the reaction was stirred at room temperature for 1 hour. Once no starting material was seen by analytical LCMS, the mixture was quenched with H₂O and extracted twice with CH₂Cl₂. The combined organic layers were dried over MgSO₄, filtered, and concentrated to give the title compound.

Step 2: (2′-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid

Prepared according to the procedure described in Example 1, Step 6 and Step 7, using the following starting materials: {6-methoxy-2′-[(2,2,2-trifluoro-ethylamino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester and acetyl chloride.

Example 5 Synthesis of {2′-[(Acetyl-ethyl-amino)-methyl]-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-10) Step 1: (3-Bromo-4-fluoro-phenyl)-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 1, using the following starting material: (3-bromo-4-fluoro-phenyl)-acetic acid.

Step 2 [4-Fluoro-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 2, using the following starting materials: (3-bromo-4-fluoro-phenyl)-acetic acid methyl ester and bis(pinacolato)diboron.

Step 3: (6-Fluoro-2′-formyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: 2-bromo-5-trifluoromethyl-benzaldehyde and [4-fluoro-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid methyl ester; the isolated product was further purified by preparative HPLC.

Step 4: (2′-Ethylaminomethyl-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 5, using the following starting materials: (6-fluoro-2′-formyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and ethylamine (2M in THF).

Step 5: {2′-[(Acetyl-ethyl-amino)-methyl]-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 6, using the following starting materials: (2′-ethylaminomethyl-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and acetyl chloride.

Step 6: {2′-[(Acetyl-ethyl-amino)-methyl]-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

The methyl ester in the product of Step 5 was hydrolyzed according to the procedure described in Example 3, Step 3.

Example 6 Synthesis of (2′-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-11) Step 1: {6-Fluoro-2′-[(2,2,2-trifluoro-ethylamino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester

Prepared according to the procedure described in Example 4, Step 1, using the following starting materials: (6-fluoro-2′-formyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and 2,2,2-trifluoroethylamine hydrochloride.

Step 2: (2′-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid

Prepared according to the procedure described in Example 1, Step 6 and Step 7, using the following starting materials: {6-fluoro-2′-[(2,2,2-trifluoro-ethylamino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester and acetyl chloride.

Example 7 Synthesis of {2′-[(Ethyl-methoxycarbonyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-23) Step 1: {2′-[(Ethyl-methoxycarbonyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester

To (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.091 g, 0.24 mmol) and triethylamine (0.05 mL, 0.36 mmol) in CH₂Cl₂ (1 mL) was added methyl chloroformate (0.03 mL, 0.36 mmol), and the mixture was stirred at room temperature for 20 minutes. Once no starting material was seen by analytical LCMS, the reaction was quenched with H₂O and diluted with CH₂Cl₂ and saturated aqueous NaHCO₃. The aqueous layer was separated and extracted with CH₂Cl₂, and the combined organic layers were dried over MgSO₄, filtered, and concentrated, and the residue was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give the title compound.

Step 2: {2′-[(Ethyl-methoxycarbonyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

Prepared according to the procedure described in Example 3, Step 3, using the following starting material: {2′-[(ethyl-methoxycarbonyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester.

{2′-[(Benzyloxycarbonyl-methyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-27) was prepared by following the procedures of Example 7 and using (6-methoxy-2′-methylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and benzyl chloroformate.

{2′-[(Benzyloxyarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-28) was prepared by following the procedures of Example 7 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and benzyl chloroformate.

Example 8 Synthesis of {2′-[(Benzyloxycarbonyl-methyl-amino)-methyl]-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-29) Step 1: (6-Fluoro-2′-methylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 5, using the following starting materials: (6-fluoro-2′-formyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and methylamine (2M in THF).

Step 2: {2′-[(Benzyloxycarbonyl-methyl-amino)-methyl]-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester

Prepared according to the procedure described in Example 7, Step 1, using the following starting materials: (6-fluoro-2′-methylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and benzyl chloroformate.

Step 3: {2′-[(Benzyloxycarbonyl-methyl-amino)-methyl]-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

The methyl ester of the product from Step 2 was hydrolyzed according to the procedure described in Example 1 Step 7.

Example 9 Synthesis of (2′-{[Ethyl-(2-methoxy-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-46) Step 1: (2′-{[Ethyl-(2-methoxy-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 6, using the following starting materials: (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and methoxyacetyl chloride.

Step 2: (2′-{[Ethyl-(2-methoxy-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid

(2′-{[Ethyl-(2-methoxy-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.135 g, 0.31 mmol) in THF (2 mL) was treated with 1N aqueous LiOH (2 mL) for 2 hours at room temperature. The mixture was acidified with 1N aqueous HCl and extracted three times with EtOAc. The combined organic layers were dried and concentrated, and the residue was purified by preparative HPLC to give the title compound.

Example 10 Synthesis of [2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-96) Step 1: [2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid methyl ester

To (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.207 g, 0.54 mmol) in CH₂Cl₂ (2 mL) at 0° C. was added diisopropylethylamine (0.21 mL, 1.19 mmol), followed by phosgene (20% in toluene; 0.34 mL, 0.65 mmol), and the reaction was stirred for 2 hours at 0° C. Benzylamine (0.09 mL, 0.81 mmol) was then added, and the reaction was stirred for 15 minutes. Triethylamine (0.1 mL, 0.72 mmol) was added, and the reaction was stirred for 1 hour. Additional benzylamine (0.09 mL, 0.81 mmol) and diisopropylethylamine (0.21 mL, 1.19 mmol) were added, and the reaction was stirred for 3 hours, until no starting material was seen by analytical LCMS. The mixture was partitioned between H₂O and CH₂Cl₂, and the aqueous layer was separated and extracted twice with CH₂Cl₂. The combined organic layers were dried and concentrated, and the residue was purified by silica gel chromatography (20-40% EtOAc in hexanes) to give the title compound.

Step 2: [2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid

Prepared according to the procedure described in Example 9, Step 2, using the following starting material: [2′-(3-benzyl-1-ethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid methyl ester.

Alternative synthesis: To (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester (prepared as described in Example 1, Step 1 but using EtOH in place of MeOH; 44.9 g, 0.114 mol) in CH₂Cl₂ (450 mL) at room temperature was added triethylamine (24 mL, 0.17 mol), followed by benzylisocyanate (16.7 mL, 0.136 mol), and the reaction was stirred for 2 hours until no starting material was seen by analytical LCMS. The mixture was partitioned between H₂O and CH₂Cl₂, and the aqueous layer was separated and extracted with CH₂Cl₂. The combined organic layers were dried (MgSO₄) and concentrated, and the residue was purified by silica gel chromatography (0-60% EtOAc in hexanes) to give the [2′-(3-benzyl-1-ethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid ethyl ester. Hydrolysis of the ethyl ester according to the procedure described in Example 1, Step 7 provided [2′-(3-benzyl-1-ethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid.

Example 11 Synthesis of (2′-Ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester Step 1: (3-Bromo-4-methoxy-phenyl)-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 1, using the following starting materials: 3-bromo-4-methoxyphenylacetic acid and ethanol.

Step 2: [4-Methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester

(3-Bromo-4-methoxy-phenyl)-acetic acid ethyl ester (27.4 g, 100.3 mmol), bis(pinacolato)diboron (25.47 g, 100.3 mmol), and potassium acetate (24.6 g, 250.8 mmol) were combined in 1,4-dioxane (250 mL) under N₂. The solution was purged with N₂, and then (1,1′-bis(diphenylphosphino)ferrocene)-dichloropalladium(II) (4.10 g, 5.02 mmol) was added and the reaction was heated to 110° C. overnight. The mixture was filtered through Celite and partitioned between EtOAc and brine. The aqueous layer was separated and extracted twice with EtOAc, and the combined organic layers were dried and concentrated. The residue was purified by silica gel chromatography (20-60% EtOAc in hexanes) to give the title compound.

Step 3: (2′-Formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: 2-bromo-5-(trifluoromethyl)benzaldehyde and [4-methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester.

Step 4: (2′-Ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester

To (2′-formyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester (1.0 g, 2.73 mmol) in MeOH (8 mL) was added ethylamine (2M in THF; 5 mL, 10 mmol), followed by acetic acid (0.23 mL, 4.09 mmol). Sodium cyanoborohydride (0.260 g, 4.14 mmol) was then added, and the reaction was stirred at room temperature and monitored by analytical LCMS. The reaction never reached completion, so the mixture was concentrated and partitioned between EtOAc and saturated aqueous NaHCO₃. The aqueous layer was extracted with EtOAc, and the combined organic layers were dried over MgSO₄, filtered, and concentrated. The residue was purified by silica gel chromatography (0-6% MeOH in CH₂Cl₂) to give the title compound.

Example 12 Synthesis of {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-6-hydroxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester Step 1: (3-Bromo-4-hydroxy-phenyl)-acetic acid

3-Bromo-4-methoxyphenylacetic acid (1.3 g, 5.6 mmol) was heated in a solution of hydrogen bromide (3 mL) and acetic acid (3 mL) at 100° C. overnight. The mixture was then partitioned between EtOAc and H₂O, and the aqueous layer was separated and extracted with EtOAc. The combined organic layers were washed with brine, dried over MgSO₄, filtered, and concentrated to give the title compound.

Step 2: (3-Bromo-4-hydroxy-phenyl)-acetic acid ethyl ester

(3-Bromo-4-hydroxy-phenyl)-acetic acid (5.6 mmol) in EtOH (20 mL) was treated with sulfuric acid (1 mL) and stirred at room temperature over the weekend. The mixture was concentrated to give the title compound.

Step 3: (2-Bromo-5-trifluoromethyl-benzyl)-ethyl-amine

Prepared according to the procedure described in Example 11, Step 4, using the following starting materials: 2-bromo-5-(trifluoromethyl)benzaldehyde and ethylamine (2M in THF).

Step 4: (2-Bromo-5-trifluoromethyl-benzyl)-ethyl-carbamic acid benzyl ester

Prepared according to the procedure described in Example 1, Step 6, using the following starting materials: (2-bromo-5-trifluoromethyl-benzyl)-ethyl-amine and benzyl chloroformate.

Step 5: Ethyl-[2-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-5-trifluoromethyl-benzyl]-carbamic acid benzyl ester

Prepared according to the procedure described in Example 11, Step 2, using the following starting materials: (2-bromo-5-trifluoromethyl-benzyl)-ethyl-carbamic acid benzyl ester and bis(pinacolato)diboron.

Step 6: {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-6-hydroxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: (3-bromo-4-hydroxy-phenyl)-acetic acid ethyl ester and ethyl-[2-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-5-trifluoromethyl-benzyl]-carbamic acid benzyl ester.

Example 13 Synthesis of {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-methanesulfonylamino-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-155) Step 1: (2-Bromo-5-nitro-phenyl)-methanol

To 2-bromo-5-nitrobenzoic acid (5 g, 20 mmol) at 0C was added borane tetrahydrofuran complex (1M in THF; 200 mL, 200 mmol), and the reaction was stirred at room temperature overnight. The mixture was quenched with 1N aqueous HCl to give the title compound.

Step 2: 2-Bromo-5-nitro-benzaldehyde

Prepared according to the procedure described in Example 1, Step 3, using the following starting material: (2-bromo-5-nitro-phenyl)-methanol.

Step 3: (2′-Formyl-6-methoxy-4′-nitro-biphenyl-3-yl)-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: 2-bromo-5-nitro-benzaldehyde and [4-methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester.

Step 4: (2′-Ethylaminomethyl-6-methoxy-4′-nitro-biphenyl-3-yl)-acetic acid ethyl ester

Prepared according to the procedure described in Example 11, Step 4, using the following starting materials: (2′-formyl-6-methoxy-4′-nitro-biphenyl-3-yl)-acetic acid ethyl ester and ethylamine (2M in THF).

Step 5: {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-nitro-biphenyl-3-yl}-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 6, using the following starting materials: (2′-ethylaminomethyl-6-methoxy-4′-nitro-biphenyl-3-yl)-acetic acid ethyl ester and benzyl chloroformate.

Step 6: {4′-Amino-2′-[(benzyloxycarbonyl-ethyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester

To a solution of {2′-[(benzyloxycarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-nitro-biphenyl-3-yl}-acetic acid ethyl ester (0.70 g, 1.75 mmol) in EtOH (70 mL) was added tin (II) chloride (1.97 g, 8.75 mmol). The reaction was heated to reflux for 5 h, and then the mixture was acidified to pH 1 with concentrated HCl and diluted with EtOAc. The resulting biphasic mixture was filtered through Celite, and the organic layer was separated. The aqueous layer was neutralized to pH 7 with solid NaOH and extracted with EtOAc. The combined organic extracts were dried and filtered, and the residue was purified by silica gel chromatography to give the title compound.

Step 8:

{4′-Amino-2′-[(benzyloxycarbonyl-ethyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester (0.080 g, 0.2 mmol), methanesulfonyl chloride (0.04 mL, 0.3 mmol), and triethylamine were reacted in CH₂Cl₂ to give {2′-[(benzyloxycarbonyl-ethyl-amino)-methyl]-4′-methanesulfonylamino-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester. {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-methanesulfonylamino-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester (0.2 mmol) was hydrolyzed with lithium hydroxide to give the title compound.

{4′-Acetylamino-2′-[(benzyloxycarbonyl-ethyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-153) was prepared according to the previous procedure using acetyl chloride instead of methanesulfonyl chloride.

Example 14 Synthesis of {4′-Bromo-2′-[(tert-butoxycarbonyl-ethyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester Step 1: 5-Bromo-2-iodo-benzaldehyde

To 5-bromo-2-iodobenzonitrile (7.4 g, 24.2 mmol) in THF (40 mL) at −78° C. was added diisobutylaluminium hydride (1M in hexanes; 24.2 mL, 24.2 mmol) over 5 minutes, and the reaction was allowed to warm to room temperature and monitored by analytical tlc. After stirring overnight at room temperature, starting material was still present, so the mixture was cooled to 0° C. and additional diisobutylaluminium hydride (1M in hexanes; 10.0 mL, 10.0 mmol) was added. After stirring for 2 hours at room temperature, no starting material was seen by analytical tlc, so the mixture was carefully quenched with freshly saturated aqueous Na₂SO₄ and diluted with EtOAc. The mixture was stirred vigorously for 1 hour and then filtered through Celite. The filtrate was concentrated, and the resulting oil solidified on standing. The solid was stirred vigorously in CH₂Cl₂ and 1N aqueous HCl, and the aqueous layer was separated and extracted with CH₂Cl₂. The combined organic layers were dried over MgSO₄, filtered, and concentrated to give the title compound.

Step 2: (5-Bromo-2-iodo-benzyl)-ethyl-amine

To 5-bromo-2-iodo-benzaldehyde (5.0 g, 16.1 mmol) in MeOH (20 mL) was added ethylamine (2M in MeOH; 16 mL, 24.0 mmol), followed by acetic acid (1.0 mL, 17.8 mmol), and the mixture was stirred at room temperature for 30 minutes. Sodium cyanoborohydride (2.0 g, 31.8 mmol) was then added over 5 minutes, and the reaction was stirred at room temperature over the weekend. The mixture was concentrated and partitioned between EtOAc and saturated aqueous NaHCO₃. The aqueous layer was extracted with EtOAc, and the combined organic layers were dried over MgSO₄, filtered, and concentrated. The residue was purified by silica gel chromatography (0-5% MeOH in CH₂Cl₂) to give the title compound.

Step 3: (5-Bromo-2-iodo-benzyl)-ethyl-carbamic acid tert-butyl ester

(5-Bromo-2-iodo-benzyl)-ethyl-amine (4.05 g, 11.9 mmol) in CH₂Cl₂ (30 mL) was treated with di-tert-butyl dicarbonate (3.12 g, 14.3 mmol) at room temperature overnight. The mixture was diluted with CH₂Cl₂ and washed with H₂O, dried over MgSO₄, filtered, and concentrated to give the title compound.

Step 4: {4′-Bromo-2′-[(tert-butoxycarbonyl-ethyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: (5-bromo-2-iodo-benzyl)-ethyl-carbamic acid tert-butyl ester and [4-methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester.

Example 15 Synthesis of (2′-{[Ethyl-(2,2,2-trifluoro-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-32)

A solution of (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.106 g, 0.28 mmol) and triethylamine (0.06 mL, 0.42 mmol) in CH₂Cl₂ (1 mL) was cooled to −78° C. Trifluoroacetic anhydride (0.06 mL, 0.42 mmol) was added, and the reaction was stirred at room temperature for 1 hour. Additional triethylamine and trifluoroacetic anhydride were added. After 2 hours, the mixture was diluted with CH₂Cl₂ and H₂O, and the aqueous layer was extracted with CH₂Cl₂. The combined organic layers were dried over Na₂SO₄, filtered, and concentrated, and the residue was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give (2′-{[ethyl-(2,2,2-trifluoro-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester. The methyl ester was hydrolyzed according to the procedure described in Example 3, Step 3.

Example 16 Synthesis of 2-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-5′-carboxymethyl-2′-methoxy-biphenyl-4-carboxylic acid (Compound 1-37) Step 1: 2-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-5′-carboxymethyl-2′-methoxy-biphenyl-4-carboxylic acid

(2′-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (0.709 g, 1.46 mmol) was dissolved in 1N aqueous NaOH (4 mL, 4 mmol) with heating, and stirred at 100° C. for 1 hour. Ethylene glycol (10 mL) was added, and the reaction was stirred at 150° C. for 3 hours. Sodium hydroxide pellets (0.727 g, 18.2 mmol) was added, and the reaction was stirred at 150° C. overnight. After cooling to room temperature, the mixture was neutralized with 1N aqueous HCl and extracted twice with CH₂Cl₂. The combined organic layers were dried over MgSO₄, filtered, and concentrated, and the residue was purified by preparative HPLC. The isolated material was repurified by preparative HPLC to give the title compound.

Example 17 Synthesis of (2′-{[(3,5-Dichloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-38) Step 1: 3,5-Dichlorobenzyl Chloroformate

To 3,5-dichlorobenzyl alcohol (0.201 g, 1.06 mmol) in CH₂Cl₂ (0.5 mL) was added phosgene (20% in toluene; 0.42 mL, 0.79 mmol), and the mixture was stirred at room temperature for 30 minutes to give the title compound, which was used directly in the next step.

Step 2: (2′-{[(3,5-Dichloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

To (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.101 g, 0.26 mmol) and diisopropylethylamine (0.23 mL, 1.32 mmol) in CH₂Cl₂ (1 mL) was added 3,5-dichlorobenzyl chloroformate (1.06 mmol) in CH₂Cl₂, and the reaction was stirred at room temperature for 5 minutes. The mixture was diluted with H₂O and extracted with CH₂Cl₂. The combined organic layers were dried over Na₂SO₄, decanted, and concentrated, and the residue was purified by silica gel chromatography to give the title compound.

Step 3: (2′-{[(3,5-Dichloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid

(2′-{[(3,5-Dichloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.088 g, 0.15 mmol) in THF (1 mL) and MeOH (0.8 mL) was hydrolyzed with 1N aqueous NaOH (0.5 mL) for 2.5 hours. The mixture was acidified with 1N aqueous HCl and extracted with CH₂Cl₂. The combined organic layers were dried over Na₂SO₄, decanted, and concentrated, and the residue was purified by preparative HPLC to give the title compound.

Example 18 Synthesis of (2′-{[(2-Chloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-39) Step 1: (2′-{[(2-Chloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

To (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.103 g, 0.27 mmol) and triethylamine (0.06 mL, 0.40 mmol) in CH₂Cl₂ (1 mL) was added 2-chlorobenzyl chloroformate (0.06 mL, 0.40 mmol), and the reaction was stirred at room temperature for 1 hour. The mixture was diluted with CH₂Cl₂ and H₂O, and the aqueous layer was extracted with CH₂Cl₂. The combined organic layers were dried over Na₂SO₄, decanted, and concentrated, and the residue was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give the title compound.

Step 2: (2′-{[(2-Chloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid

(2′-{[(2-Chloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.27 mmol) in THF (1 mL) and MeOH (0.8 mL) was hydrolyzed with 1N aqueous NaOH (0.7 mL) for 1 hour. The mixture was acidified with 1N aqueous HCl and extracted with CH₂Cl₂. The combined organic layers were dried over MgSO₄, filtered, and concentrated to give the title compound.

(2′-{[(3,5-Difluoro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-40) was prepared by following the procedures outlined in Example 18 and using 3,5-difluorobenzyl alcohol.

(2′-{[Ethyl-(4-fluoro-benzyloxycarbonyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-41) was prepared by following the procedures outlined in Example 18 and using 4-fluorobenzyl alcohol.

(2′-{[(4-Chloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-42) was prepared by following the procedures outlined in Example 18 and using 4-chlorobenzyl alcohol.

(2′-{[(3-Chloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-43) was prepared by following the procedures outlined in Example 18 and using 3-chlorobenzyl alcohol.

[2′-({[1-(4-Chloro-phenyl)-ethoxycarbonyl]-ethyl-amino}-methyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-44) was prepared by following the procedures outlined in Example 18 and using 1-(4-chlorophenyl)ethanol.

Example 19 Synthesis of (2′-{[Benzyloxycarbonyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-49)

{6-Fluoro-2′-[(2,2,2-trifluoro-ethylamino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester (0.26 g, 0.62 mmol), benzyl chloroformate (0.13 mL, 0.93 mmol), and triethylamine (0.13 mL, 0.93 mmol) were combined in CH₂Cl₂ (2.1 mL), and the reaction was stirred at room temperature for 2 hours. Additional benzyl chloroformate (0.13 mL, 0.93 mmol), and triethylamine (0.13 mL, 0.93 mmol) were added, and the reaction was stirred for 1 hour. Starting material was still present, so an aqueous work-up was performed, and the residue was dissolved in DMF and cooled to 0° C. Sodium hydride (60% in mineral oil; 0.030 g, 0.75 mmol) was added, followed by benzyl chloroformate (0.13 mL, 0.93 mmol), and the reaction was stirred for 20 minutes. The mixture was worked up with CH₂Cl₂ and H₂O, and the organic layer was dried over MgSO₄, filtered, and concentrated. The residue was purified by silica gel chromatography to give (2′-{[benzyloxycarbonyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester. The ester was hydrolyzed according to the procedure described in Example 17, Step 3.

Example 20 Synthesis of {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-143) Step 1: (3-Bromo-phenyl)-acetic acid methyl ester

To 3-bromophenylacetic acid (5.03 g, 23.4 mmol) in MeOH (50 mL) was added thionyl chloride (3.4 mL, 46.8 mmol), and the reaction was stirred at 65° C. for 5 hours. The mixture was concentrated, and the residue was partitioned between CH₂Cl₂ and saturated aqueous NaHCO₃. The mixture was basified with 1N aqueous NaOH, and the aqueous layer was extracted with CH₂Cl₂. The combined organic layers were washed with H₂O, dried over MgSO₄, filtered, and concentrated to give the title compound.

Step 2: [3-(4,4,5,5-Tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 2, using the following starting materials: (3-bromo-phenyl)-acetic acid methyl ester and bis(pinacolato)diboron.

Step 3: (2′-Formyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: [3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid methyl ester and 2-bromo-5-(trifluoromethyl)benzaldehyde.

Step 4: (2′-Ethylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 5, using the following starting materials: (2′-formyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and ethylamine (2M in THF).

Step 5: {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester

Prepared according to the procedure described in Example 1, Step 6, using the following starting materials: (2′-ethylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester and benzyl chloroformate.

Step 6: {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

Prepared according to the procedure described in Example 3, Step 3, using the following starting material: {2′-[(benzyloxycarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid methyl ester.

Example 21 Synthesis of {2′-[1-Ethyl-3-(4-hydroxy-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-252) Step 1: {2′-[1-Ethyl-3-(4-hydroxy-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester

To (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester (0.59 g, 1.49 mmol) and diisopropylethylamine (0.65 mL, 3.73 mmol) in CH₂Cl₂ (6 mL) at 0° C. was added phosgene (20% in toluene; 1.2 mL, 2.24 mmol), and the reaction was stirred for 1 hour. 4-Hydroxybenzylamine (0.278 g, 2.24 mmol) and triethylamine (1 mL, 7.47 mmol) were then added, and the reaction was stirred for 2 hours. Additional 4-hydroxybenzylamine (0.184 g, 1.49 mmol) was added, and the reaction was stirred for another 30 minutes. The mixture was partitioned between CH₂Cl₂ and H₂O, and the organic layer was dried over MgSO₄, filtered, and concentrated. The residue was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give the title compound.

Step 2: {2′-[1-Ethyl-3-(4-hydroxy-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

{2′-[1-Ethyl-3-(4-hydroxy-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester (0.535 g, 0.98 mmol) in THF (5 mL) and EtOH (4 mL) was treated with 1N aqueous NaOH (3 mL), and the reaction was stirred for 2.5 hours. Analytical LCMS indicated that starting material was still present, so additional 1N aqueous NaOH was added, and the reaction was heated with a heat gun. Once no starting material was seen by analytical LCMS, the mixture was worked-up with CH₂Cl₂ and 1N aqueous HCl, and the organic layer was dried over MgSO₄, filtered, and concentrated to give the title compound.

{2′-[1-Ethyl-3-(2-hydroxy-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-253) was prepared by following the procedures outlined in Example 21 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester and 2-hydroxybenzylamine.

{2′-[1-Ethyl-3-(3-hydroxy-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-257) was prepared by following the procedures outlined in Example 21 and using (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester and 3-(aminomethyl)phenol.

Example 22 Synthesis of [2′-({[2-(4-Chloro-phenoxy)-2-methyl-propionyl]-ethyl-amino}-methyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-118) Step 1: 2-(4-Chloro-phenoxy)-2-methyl-propionic acid

A solution of 2-(4-chlorophenoxy)isobutyric acid ethyl ester (1.0 g, 4.12 mmol) in THF (10 mL) was treated with 1N aqueous LiOH (10 mL) and stirred overnight at room temperature. The mixture was acidified with 1N aqueous HCl to pH 3-4 and extracted three times with EtOAc. The combined organic layers were dried and concentrated to give the title compound.

Step 2: 2-(4-Chloro-phenoxy)-2-methyl-propionyl chloride

2-(4-Chloro-phenoxy)-2-methyl-propionic acid (0.124 g, 0.58 mmol) and triethylamine (0.09 mL, 0.62 mmol) were combined in CH2Cl2 (2 mL) and cooled to 0C. Oxalyl chloride (0.05 mL, 0.62 mmol) was added, followed by DMF (3 drops), and the mixture was slowly warmed to room temperature and stirred for 2 hours to give the title compound, which was used directly in the next step.

Step 3: [2′-({[2-(4-Chloro-phenoxy)-2-methyl-propionyl]-ethyl-amino}-methyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid

To a solution of 2-(4-chloro-phenoxy)-2-methyl-propionyl chloride (0.58 mmol) in CH₂Cl₂ was added (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.200 g, 0.52 mmol) in triethylamine (0.17 mL, 1.23 mmol), and the reaction was stirred at room temperature for 30 minutes. The mixture was concentrated and purified by silica gel chromatography (10-30% EtOAc in hexanes) to give [2′-({[2-(4-chloro-phenoxy)-2-methyl-propionyl]-ethyl-amino}-methyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid methyl ester. The ester was hydrolyzed according to the procedure described in Example 9, Step 2.

Example 23 Synthesis of {2′-[3-(4-Chloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-140) Step 1: {2′-[3-(4-Chloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester

To (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester (0.196 g, 0.50 mmol) in CH₂Cl₂ (2 mL) at 0° C. was added diisopropylethylamine (0.21 mL, 1.24 mmol), followed by phosgene (20% in toluene, 0.39 mL, 0.75 mmol), and the mixture was stirred for 3 hours. 4-Chlorobenzylamine (0.09 mL, 0.75 mmol) was added, followed by triethylamine (0.14 mL, 1.0 mmol), and the reaction was stirred at room temperature for 20 minutes. Additional triethylamine (0.07 mL, 0.5 mmol) was added, and the reaction was stirred for 1 hour and then worked-up with CH₂Cl₂ and H₂O. The organic layer was dried and concentrated, and the residue was purified by silica gel chromatography (0-50% EtOAc in hexanes) to give the title compound.

Step 2: {2′-[3-(4-Chloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

To {2′-[3-(4-chloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester (0.196 g, 0.35 mmol) in THF (2 mL) and MeOH (2 mL) was added 1N aqueous LiOH (2 mL), and the reaction was stirred at room temperature for 2 hours. The mixture was acidified with 1N aqueous HCl and extracted three times with EtOAc, and the combined organic layers were dried and concentrated. The residue was purified by preparative HPLC to give the title compound.

Example 24 Synthesis of {2′-[3-(3,4-Dichloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-152)

(2′-Ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester (0.17 g, 0.42 mmol) and triethylamine (0.12 mL, 0.86 mmol) were combined in CH₂Cl₂ (2 mL). 3,4-Dichlorobenzyl isocyanate (0.08 mL, 0.52 mmol) was added, and the reaction was stirred at room temperature for 15 minutes. After concentrating, the crude material was purified by silica gel chromatography (20-50% EtOAc in hexanes) to give {2′-[3-(3,4-dichloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester. The ethyl ester was hydrolyzed according to the procedure described in Example 23, Step 2.

[2′-(3-Benzyl-1-ethyl-ureidomethyl)-4′-fluoro-6-methoxy-biphenyl-3-yl]-acetic acid (Compound 1-187) was prepared by following the procedures of Example 24 and using (2′-ethylaminomethyl-4′-fluoro-6-methoxy-biphenyl-3-yl)-acetic acid ethyl ester and benzyl isocyanate. Example 25 Synthesis of {2′-[3-(3,5-Dichloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-165) Step 1: {2′-[3-(3,5-Dichloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester

To a solution of (2′-ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester (0.170 g, 0.43 mmol) in CH₂Cl₂ (2 mL) at 0° C. was added diisopropylethylamine (0.19 mL, 1.08 mmol), followed by phosgene (20% in toluene; 0.34 mL, 0.64 mmol), and the mixture was stirred for 1.5 hours. 3,5-Dichlorobenzylamine (0.091 g, 0.52 mmol) was added, followed by triethylamine (0.12 mL, 0.86 mmol), and the reaction was warmed to room temperature and stirred for 45 minutes. Additional triethylamine (0.12 mL, 0.86 mmol) was added, and the reaction was stirred for 1.5 hours. Another portion of triethylamine (0.25 mL, 17.9 mmol) was added, and the reaction was stirred overnight at room temperature. The mixture was worked up with CH₂Cl₂ and H₂O, and the aqueous layer was extracted twice with CH₂Cl₂The combined organic layers were dried and concentrated, and the residue was purified by silica gel chromatography (0-50% EtOAc in hexanes) to give the title compound.

Step 2: {2′-[3-(3,5-Dichloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

Prepared according to the procedure described in Example 23, Step 2, using the following starting material: {2′-[3-(3,5-dichloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester.

The following compounds were also prepared by the procedures of Example 25:

-   {2′-[1-Ethyl-3-(4-fluoro-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic     acid (Compound 1-176) was prepared by using 4-fluorobenzylamine. -   {2′-[3-(3-Chloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic     acid (Compound 1-177) was prepared by using 3-chlorobenzylamine. -   {2′-[3-(3,5-Difluoro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic     acid (Compound 1-178) was prepared by using 3,5-difluorobenzylamine. -   (2′-{3-[(R)-1-(4-Chloro-phenyl)-ethyl]-1-ethyl-ureidomethyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic     acid (Compound 1-179) was prepared by using     (R)-(+)-1-(4-chlorophenyl)ethylamine. -   (2′-{3-[(S)-1-(4-Chloro-phenyl)-ethyl]-1-ethyl-ureidomethyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic     acid (Compound 1-180) was prepared by using     (S)-4-chloro-alpha-methylbenzylamine. -   [2′-(1,3-Diethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic     acid (Compound 1-181) was prepared by using ethylamine (2M in THF).

Example 26 Synthesis of {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-244) Step 1: (2′-Ethylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid

{2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (0.16 g, 0.34 mmol) in EtOH (7 mL) was treated with 10% palladium on carbon (0.072 g), and the reaction was stirred under a balloon of H₂ for 3 hours to give the title compound.

Step 2: (2′-Ethylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester

To a solution of (2′-ethylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (0.34 mmol) in EtOH (7 mL) was added sulfuric acid (3-4 drops), and the reaction was stirred at 50° C. overnight. Once no starting material was seen by analytical LCMS, the mixture was filtered over a pad of Celite and rinsed with EtOH. The filtrate was concentrated to give the title compound.

Step 3: {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 6, using the following starting materials: (2′-ethylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester and cyclopropanecarbonyl chloride.

Step 4: {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid

The ethyl ester from Step 3 was hydrolyzed according to the procedure described in Example 23, Step 2.

Example 27 Synthesis of [2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-hydroxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid ethyl ester Step 1: [4-Benzyloxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 2, using the following starting materials: (4-benzyloxy-3-bromo-phenyl)-acetic acid ethyl ester and bis(pinacolato)diboron.

Step 2: (6-Benzyloxy-2′-formyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: [4-benzyloxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester 2-bromo-5-(trifluoromethyl)benzaldehyde.

Step 3: (6-Benzyloxy-2′-ethylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 5, using the following starting materials: (6-benzyloxy-2′-formyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester and ethylamine (2M in THF).

Step 4: [2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-benzyloxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid ethyl ester

Prepared according to the procedure described in Example 24, Step 1, using the following starting materials: (6-benzyloxy-2′-ethylaminomethyl-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid ethyl ester and benzyl isocyanate.

Step 5: [2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-hydroxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid ethyl ester

[2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-benzyloxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid ethyl ester (0.580 g, 0.96 mmol) in EtOAc was treated with 10% palladium on carbon (catalytic) and stirred under a balloon of H₂ overnight. Analytical tlc indicated that some starting material was still present, so fresh palladium on carbon was added, and the reaction was stirred under a balloon of H₂ for an additional 24 hours. Once no starting material was seen by analytical tlc, the mixture was filtered over Celite, and the filtrate was concentrated and purified by silica gel chromatography to give the title compound.

Example 28 [2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-hydroxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-220)

Hydrolysis of the ethyl ester of [2′-(3-benzyl-1-ethyl-ureidomethyl)-6-hydroxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid ethyl ester provides the title compound.

Example 29 Synthesis of 2-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-5′-carboxymethyl-2′-methoxy-biphenyl-4-carboxylic acid (Compound 1-226) Step 1: 4-Bromo-3-methyl-benzoic acid ethyl ester

To 4-bromo-3-methylbenzoic acid (16.27 g, 75.7 mmol) in EtOH (500 mL) was added concentrated sulfuric acid (0.5 mL), and the reaction was stirred at 95° C. overnight. Additional sulfuric acid (2 mL) was added and then the mixture was quenched with the slow addition of sodium carbonate. The mixture was filtered and concentrated, and the residue was diluted and washed with H₂O twice, saturated aqueous NaHCO₃, brine, and H₂O to give the title compound.

Step 2: 4-Bromo-3-bromomethyl-benzoic acid ethyl ester

4-Bromo-3-methyl-benzoic acid ethyl ester (18.24 g, 75.4 mmol), N-bromosuccinimide (14.1 g, 79.2 mmol), and benzoyl peroxide (0.9 g, 3.77 mmol) were combined in CC14, and the reaction was heated to 80° C. and stirred with a halogen desk lamp shining on it for 6 hours. The mixture was concentrated and partitioned between CH₂Cl₂ and H₂O. The organic layer was separated and washed with H₂O and brine, and then dried and concentrated. The residue was triturated with hexane (3×50 mL) and dried to give the title compound.

Step 3: Ethyl-carbamic acid benzyl ester

Ethylamine (1.3 mL, 20.0 mmol) and diisopropylethylamine (7 mL, 40.0 mmol) were combined in CH₂Cl₂ (200 mL) and cooled to 0° C. Benzyl chloroformate (2.86 mL, 20.0 mmol) was added dropwise, and the reaction was stirred at 0° C. for 30 minutes. Once no starting material was seen by analytical tlc, the mixture was warmed to room temperature and washed with H₂O, 0.1N aqueous HCl, and H₂O, and then dried and concentrated to give the title compound.

Step 4: 3-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4-bromo-benzoic acid ethyl ester

4-Bromo-3-bromomethyl-benzoic acid ethyl ester (2.95 g, 9.2 mmol) and ethyl-carbamic acid benzyl ester (3.30 g, 18.4 mmol) were combined in DMF (100 mL) and cooled to 0° C. Sodium hydride (60% in mineral oil; 0.772 g, 19.3 mmol) was added slowly, and the reaction was stirred at room temperature for 10 minutes. The mixture was quenched with H₂O and 1N aqueous HCl (20 mL), and then extracted with 1:1 EtOAc:hexanes three times. The organic layer was washed with brine, and then dried and concentrated. The residue was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give the title compound, as well as the hydrolyzed product, which was combined with the product from the next step.

Step 5: 3-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4-bromo-benzoic acid

3-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4-bromo-benzoic acid ethyl ester (3.62 g, 7.2 mmol) was dissolved in MeOH (40 mL) and cooled to 0° C. 1N Aqueous LiOH (22 mL, 22 mmol) was added, and the reaction was stirred at room temperature for 3 hours. The mixture was quenched with 1N aqueous HCl (22 mL) and extracted three times with EtOAc. The combined organic layers were washed with brine, dried, and concentrated to give the title compound, which was combined with the hydrolyzed product isolated in step 5.

Step 6

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: 3-[(benzyloxycarbonyl-ethyl-amino)-methyl]-4-bromo-benzoic acid and [4-methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester. The ethyl ester was then hydrolyzed with 1N aqueous LiOH in THF at room temperature to give the title compound.

Example 30 Synthesis of [2′-(3-Benzyl-1,3-diethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-94) Step 1: N-Ethyl-N-benzylcarbamoyl Chloride

N-Ethylbenzylamine (0.56 mL, 3.8 mmol) and diisopropylethylamine (1 mL, 5.7 mmol) were combined in CH₂Cl₂ (12 mL) and cooled to 0° C. Phosgene (20% in toluene; 2.4 mL, 4.6 mmol) was added, and the reaction was stirred overnight at room temperature. The mixture was concentrated, and the residue was dissolved in Et₂O and washed twice with H₂O. The organic layer was dried, filtered, and concentrated to give the title compound.

Step 2: (2′-Ethylaminomethyl-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid methyl ester (0.130 g, 0.34 mmol), N-ethyl-N-benzylcarbamoyl chloride (0.08 1 g, 0.41 mmol), 4-dimethylaminopyridine (0.010 g, 0.08 mmol), and triethylamine (0.12 mL, 0.85 mmol) were combined in CH₂Cl₂ (5 mL) and stirred at reflux overnight. The mixture was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give [2′-(3-Benzyl-1,3-diethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid methyl ester. The ethyl ester was then hydrolyzed with 1N aqueous LiOH in THF at room temperature to give the title compound. Example 31 Synthesis of {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-183) Step 1: (4′-Fluoro-2′-formyl-6-methoxy-biphenyl-3-yl)-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: 2-bromo-5-fluorobenzaldehyde and [4-methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester.

Step 2: (2′-Ethylaminomethyl-4′-fluoro-6-methoxy-biphenyl-3-yl)-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 5, using the following starting materials: (4′-Fluoro-2′-formyl-6-methoxy-biphenyl-3-yl)-acetic acid ethyl ester and ethylamine (2M in THF).

Step 3: {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid

(2′-Ethylaminomethyl-4′-fluoro-6-methoxy-biphenyl-3-yl)-acetic acid ethyl ester (0.172 g, 0.5 mmol) and diisopropylethylamine (0.18 mL, 1.0 mmol) were combined in CH₂Cl₂ (2.5 mL) and cooled to 0° C. chloroformate (0.1 mL, 0.7 mmol) was added, and the reaction was stirred for 1 hour. The mixture was purified by silica gel chromatography, and then further purified by preparative HPLC to give {2′-[(benzyloxycarbonyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester. The ethyl ester was hydrolyzed to give the title compound.

{2′-[(Acetyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-184) was prepared by reacting (2′-ethylaminomethyl-4′-fluoro-6-methoxy-biphenyl-3-yl)-acetic acid ethyl ester and acetyl chloride according to the procedure described in Example 1, Step 6 and then hydrolyzing the ester with aqueous LiOH in THF at room temperature.

{2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-186) was prepared by reacting (2′-ethylaminomethyl-4′-fluoro-6-methoxy-biphenyl-3-yl)-acetic acid ethyl ester and cyclopropanecarbonyl chloride according to the procedure described in Example 1, Step 6 and then hydrolyzing the ester with aqueous LiOH in THF at room temperature

Example 32 Synthesis of {2′-[3-(4-Chloro-benzyl)-1-ethyl-ureidomethyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-185)

(2′-Ethylaminomethyl-4′-fluoro-6-methoxy-biphenyl-3-yl)-acetic acid ethyl ester (0.172 g, 0.5 mmol) and diisopropylethylamine (0.43 mL, 2.5 mmol) were combined in CH₂Cl₂ (2.5 mL) and cooled to 0° C. Phosgene (20% in toluene; 0.40 mL, 0.75 mmol) was added, and the mixture was stirred for 1 hour. 4-Chlorobenzylamine (0.012 mL, 1.0 mmol) was added, and the reaction was stirred for 1 hour. The mixture was diluted with CH₂Cl₂ and washed with H₂O. The organic layer was dried, filtered, and concentrated, and the residue was purified by preparative HPLC to give {2′-[3-(4-chloro-benzyl)-1-ethyl-ureidomethyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester. The ethyl ester was hydrolyzed with LiOH in THF at room temperature to provide the title compound.

Example 33 Synthesis of {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-methanesulfonyl-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-215) Step 1: 2-Hydroxy-5-methanesulfonyl-benzaldehyde

5-Bromosalicylaldehyde (0.402 g, 2.0 mmol), sodium methanesulfinate (0.918 g, 9.0 mmol), and copper(I) iodide (1.71 g, 9.0 mmol) were combined in NMP (16 mL) and stirred under N₂ at 140° C. overnight. The mixture was diluted with 1:1 EtOAc:hexanes (150 mL) and filtered through a pad of Celite. The filtrate was washed three times with H₂O, and then dried, filtered, and concentrated. The residue was purified by silica gel chromatography (0-100% EtOAc in hexanes) to give the title compound.

Step 2: 2-Ethylaminomethyl-4-methanesulfonyl-phenol

2-Hydroxy-5-methanesulfonyl-benzaldehyde (0.200 g, 1.0 mmol), ethylamine (2M in THF; 0.75 mL, 1.5 mmol), and sodium cyanoborohydride (0.095 g, 1.5 mmol) were combined in MeOH (10 mL). 4 Å Molecular sieves were added, followed by acetic acid (0.09 mL, 1.5 mmol), and the reaction was stirred for 1 hour. The mixture was filtered, and H₂O (0.5 mL) was added and the solution was concentrated. The residue was partitioned between EtOAc (100 mL) and brine (20 mL), and the mixture was neutralized with 1N aqueous HCl (1 mL) and extracted six times with EtOAc, until minimal product was seen in the aqueous layer by analytical tlc. The combined organic layers were dried, filtered, and concentrated to give the title compound.

Step 3: Ethyl-(2-hydroxy-5-methanesulfonyl-benzyl)-carbamic acid benzyl ester

To 2-ethylaminomethyl-4-methanesulfonyl-phenol (0.229 g, 1.0 mmol) and diisopropylamine (0.94 mL, 2.5 mmol) in CH₂Cl₂ (10 mL) was added benzyl chloroformate (0.16 mL, 1.1 mmol). Some over-acylation product was observed, so additional benzyl chloroformate (0.21 mL) was added to convert all of the product to the diacylated product. After aqueous work-up, the organic layer was concentrated, and the residue was dissolved in MeOH (10 mL) and treated with 1N aqueous LiOH (4 mL). Once the hydrolysis was complete, the mixture was worked-up, and the residue was purified to give the title compound.

Step 4: Trifluoro-methanesulfonic acid 2-[(benzyloxycarbonyl-ethyl-amino)-methyl]-4-methanesulfonyl-phenyl ester

Ethyl-(2-hydroxy-5-methanesulfonyl-benzyl)-carbamic acid benzyl ester (0.200 g, 0.55 mmol) and diisopropylethylamine (0.24 mL, 1.38 mmol) were combined in CH₂Cl₂ (10 mL). Trifluoromethanesulfonic anhydride (0.11 mL, 0.65 mmol) was added, and the reaction was stirred for 5 minutes at room temperature. The mixture was quenched with H₂O and diluted with CH₂Cl₂. The organic layer was dried, filtered, and concentrated, and the residue was purified by silica gel chromatography (0-50% EtOAc in hexanes) to give the title compound.

Step 5: {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-methanesulfonyl-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester

Trifluoro-methanesulfonic acid 2-[(benzyloxycarbonyl-ethyl-amino)-methyl]-4-methanesulfonyl-phenyl ester (1.3 g, 2.62 mmol), [4-methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester (1.26 g, 3.93 mmol), and cesium carbonate (2.55 g, 7.85 mmol) were combined in DMF. (1,1′-Bis(diphenylphosphino)ferrocene)-dichloropalladium(II) (0.213 g, 0.26 mmol) was added, and the reaction was immediately immersed in an oil bath pre-heated to 45° C. The reaction was stirred at 65° C. for 20 minutes, and then worked-up and purified to give the title compound, contaminated with a phenol by-product. The mixture was dissolved in CH₂Cl₂ (100 mL) and washed with 0.5N aqueous NaOH, and then concentrated to give the title compound.

Step 6: {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-methanesulfonyl-6-methoxy-biphenyl-3-yl}-acetic acid

The ethyl ester was hydrolyzed according to the procedure described in Example 9, Step 2.

Example 34 Synthesis of [2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-(1-hydroxy-1-methyl-ethyl)-6-methoxy-biphenyl-3-yl]-acetic acid (Compound 1-216) Step 1: 4-Bromo-3-methyl-benzoic acid ethyl ester

4-bromo-3-methylbenzoic acid (3 g, 14 mmol) in EtOH (200 mL) was added thionyl chloride (2 mL, 28 mmol), and the reaction was stirred for 10 minutes. Additional thionyl chloride (3 mL, 35 mmol) was added, and the reaction was stirred overnight at 50° C. After cooling to room temperature, the mixture was quenched with the slow addition of powdered Na₂CO₃, and then filtered and concentrated. The residue was partitioned between EtOAc and H₂O, and the organic layer was dried, filtered, and concentrated to give the title compound.

Step 2: 2-(4-Bromo-3-methyl-phenyl)-propan-2-ol

To 4-bromo-3-methyl-benzoic acid ethyl ester (0.968 g, 4.0 mmol) in THF (50 mL) at 0° C. was methylmagnesium bromide (3M in Et₂O; 4 mL, 12 mmol), and the reaction was stirred at 1 hour at 0° C. and then warmed to room temperature. Additional methylmagnesium bromide (3M in Et₂O; 4 mL, 12 mmol) was added, and the reaction was stirred for 30 minutes. The mixture was quenched with saturated aqueous NH₄Cl and partitioned between EtOAc and H₂O. The organic layer was dried, filtered, and concentrated to give the title compound.

Step 3: 2-(4-Bromo-3-bromomethyl-phenyl)-propan-2-ol

2-(4-Bromo-3-methyl-phenyl)-propan-2-ol (0.916 g, 4.0 mmol) in CCl₄ (30 mL) was treated with N-bromosuccinimide (0.750 g, 4.2 mmol) and benzoyl peroxide (0.050 g, 0.2 mmol), and the reaction was refluxed under a halogen lamp for 2 hours. After cooling to room temperature, the mixture was partitioned between CH₂Cl₂ and H₂O, and the organic layer was dried, filtered, and concentrated. The residue was purified by silica gel chromatography to give the title compound.

Step 4: [2-Bromo-5-(1-hydroxy-1-methyl-ethyl)-benzyl]-ethyl-carbamic acid benzyl ester

To 2-(4-bromo-3-bromomethyl-phenyl)-propan-2-ol (0.255 g, 0.83 mmol) and ethyl-carbamic benzyl ester (0.446 g, 2.49 mmol) in DMF (15 mL) was added sodium hydride (60% in mineral oil; 0.103 g, 2.57 mmol), and the reaction was stirred for 30 minutes. The mixture was quenched with H₂O and worked-up. The residue was purified by silica gel chromatography (0-40% EtOAc in hexanes) to give the title compound.

Step 5: [2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-(1-hydroxy-1-methyl-ethyl)-6-methoxy-biphenyl-3-yl]-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 4, using the following starting materials: [2-bromo-5-(1-hydroxy-1-methyl-ethyl)-benzyl]-ethyl-carbamic acid benzyl ester and [4-methoxy-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-acetic acid ethyl ester.

Step 6: [2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-(1-hydroxy-1-methyl-ethyl)-6-methoxy-biphenyl-3-yl]-acetic acid

The ethyl ester was hydrolyzed according to the procedure described in Example 9, Step 2.

Example 35 Synthesis of {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-methylsulfanyl-biphenyl-3-yl}-acetic acid (Compound 1-241) Step 1: {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester

Prepared according to the procedure described in Example 1, Step 6, using the following starting materials: (2′-ethylaminomethyl-4′-fluoro-6-methoxy-biphenyl-3-yl)-acetic acid ethyl ester and cyclopropanecarbonyl chloride.

Step 2: {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-methylsulfanyl-biphenyl-3-yl}-acetic acid

To {2′-[(cyclopropanecarbonyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid ethyl ester 0.186 g, 0.45 mmol) in DMF (0.5 mL) was added sodium thiomethoxide (0.035 g, 0.50 mmol), and the reaction was stirred at 85° C. for 2 hours. Additional sodium thiomethoxide (0.070 g, 1.0 mmol) was added, and the reaction was stirred at 85° C. for another 2 hours. An aqueous work-up was performed, and the residue was purified by preparative HPLC to give the title compound.

Mass spectrometric data for select compounds are displayed in Table 1.

Example 36 CRTH2 Assays Example 36a DP₂/CRTH2 binding assay

The ability of a compound to bind to the human DP₂ receptor is assessed via a radioligand binding assay using [³H]PGD₂. HEK293 cells stably expressing recombinant human DP₂ are resuspended in 10 mM Hepes, 7.4 containing 1 mM DTT, lysed and centrifuged at 75,000×g to pellet the membranes. The membranes are resuspended in 10 mM Hepes, 7.4 containing 1 mM DTT and 10% glycerol to approximately 5 mg protein/ml. Membranes (2-10 μg protein/well) are incubated in 96-well plates with 1 nM [³H]PGD₂ and test compound in Assay Buffer (50 mM Hepes, 10 mM MnCl₂, 1 mM EDTA, plus or minus 0.2% human serum albumin, pH 7.4) for 60 minutes at room temperature. The reactions are terminated by rapid filtration through Whatman GF/C glass fibre filter plates. The filter plates were pre-soaked in 0.33% polythylenimine for 30 minutes at room temperature then washed in Wash Buffer (50 mM Hepes, 0.5 M NaCl pH 7.4) prior to harvesting. After harvesting, the filter plates are washed 3 times with 1 ml cold Wash Buffer then dried. Scintillant is then added to the plates and the radioactivity retained on the filters is determined on a Packard TopCount (Perkin Elmer). Specific binding is determined as total radioactive binding minus non-specific binding in the presence of 10 μM PGD₂. IC₅₀s were determined using GraphPad prism analysis of drug titration curves. Compounds tested had an IC₅₀ of less than 20 micromolar in this assay.

Example 36b GTPγS Binding Assay

The ability of a compound to inhibit binding of GTP to DP₂ is assessed via a membrane GTPγS assay. CHO cells stably expressing the recombinant human CRTH2 receptor are resuspended in 10 mM Hepes, 7.4 containing 1 mM DTT, lysed and centrifuged at 75,000×g to pellet the membranes. The membranes are resuspended in 10 mM Hepes, 7.4 containing 1 mM DTT and 10% glycerol. Membranes (˜12.5 pg per well) are incubated in 96-well plates with 0.05 nM [³⁵S]-GTPγS, 80 nM PGD₂, 5 μM GDP, and test compound in Assay Buffer (50 mM Hepes, pH 7.4, 100 mM NaCl, 5 mM MgCl₂ and 0.2% human serum albumin) for 60 minutes at 30° C. The reactions are terminated by rapid filtration through Whatman GF/B glass fibre filter plates. The filter plates are washed 3 times with 1 ml cold Assay Buffer and dried. Scintillant is then added to the plates and the radioactivity retained on the filters is determined on a Packard TopCount (Perkin Elmer). Specific binding is determined as total radioactive binding minus non-specific binding in the absence of the ligand (80 nM PGD₂). IC₅₀s were determined using Graphpad prism analysis of drug titration curves.

Example 36c Whole Blood Esoinophil Shape Change Assay

Blood is drawn from consenting human volunteers in EDTA vacutainer tubes and used within 1 hr of draw. A 98 μl aliquot of blood is mixed with 2 μl of test compound (in 50% DMSO) in 1.2 ml polypropylene tubes. The blood is vortexed and incubated at 37° C. for 15 minutes. 5 μl of 1 μM PGD₂ in PBS is added for a final concentration of 50 nM and the tubes briefly vortexed. The reactions are incubated for exactly 5 minutes at 37° C. and then terminated by placing the tubes on ice and immediately adding 250 μl of ice-cold 1:4 diluted Cytofix (BD Biosciences). The reactions are transferred to 12×75 mM polystyrene round bottom tubes and the red blood cells lysed by the addition of 3 ml ammonium chloride lysing solution (150 mM NH₄Cl, 10 mM KHCO₃, 0.1 mM EDTA disodium salt) and incubation at room temperature for 15 minutes. The cells are pelleted by spinning at 1300 rpm for 5 minutes at 4° C. and washed once with 3 ml ice-cold PBS. The cells are resuspended in 0.2 ml of ice-cold 1:4 diluted Cytofix (BD Biosciences) and analyzed on a FACSCalibur (BD Biosciences) within 2 hours. Eosinophils were gated on the basis of autofluorescence in the FL2 channel and shape change on 500 eosinophils was assayed by forward scatter and side scatter analysis. The specific change in shape induced by PGD₂ was calculated as the difference between the percentage of high forward scatter eosinophils in the presence and absence of PGD₂. IC₅₀s were determined using Graphpad Prism® analysis of drug titration curves.

Example 36d DP₁ binding assay

The ability of a compound to bind to the human DP1 receptor was evaluated via a radioligand membrane binding assay using the DP₁ selective synthetic ligand [³H]BWA868C. Packed human platelets (Biological Specialty Corporation), were resuspended in 6 volumes of Hepes/HBSS buffer (10 mM Hepes, 1 mM DTT in Hanks Balanced Salt Solution (HBSS)), lysed and centrifuged at 75,000×g to pellet the membranes. Membranes were resuspended in Hepes/HBSS buffer to approximately 12 mg protein/ml. Membranes (20 μg protein/well) are incubated in 96-well plates with 2 nM [³H]BWA868C and test compound in Assay Buffer (50 mM Hepes, 10 mM MnCl₂, 1 mM EDTA, plus or minus 0.2% human serum albumin, pH 7.4) for 60 minutes at room temperature. The reactions are terminated by rapid filtration through Whatman GF/C glass fibre filter plates. The filter plates were pre-soaked in 0.33% polethylenimine for 30 minutes at room temperature then washed in Wash Buffer (50 mM Hepes, 0.5 M NaCl pH 7.4) prior to harvesting. After harvesting, the filter plates are washed 3 times with 1 ml cold Wash Buffer then dried. Scintillant is then added to the plates and the radioactivity retained on the filters is determined on a Packard TopCount (Perkin Elmer). Specific binding is determined as total radioactive binding minus non-specific binding in the presence of 10 μM BW A868C. IC₅₀s were determined using GraphPad prism analysis of drug titration curves.

Example 37 Mouse Allergic Rhinitis Model

The compounds ability to inhibit allergen-induced sneezing and nasal rubbing is assessed using a mouse model of allergic rhinitis. Methods were adapted from those detailed in Nakaya, M., et al. 2006, Laboratory Investigation, 86:917-926. Female BALB/c mice (20-25 g) are immunized by an intraperitoneal injection (i.p.) of 2 pg ovalbumin (OVA) complexed with alum in a volume 0.2 ml on days 0 and 14. Seven days later (day 21) mice are challenged intranasally with 20 μl of a 10mg/ml solution of OVA. The challenge period occurs daily from days 21 to day 25. Mice (5-7/ group) are randomly assigned to receive either compound or vehicle and are treated by oral gavage 1-2 hour prior to each OVA challenge. The number of sneezes and nasal rubs are counted by an independent blind observe during a period of 8 minutes immediately following OVA challenge on days 21, 23 and 25. A significant increase in allergen-induced sneezing and nasal rubbing occurs over the 5-day challenge period. Inhibition of this effect by select compounds is determined statistically using Graphpad prism.

Example 38 Guinea Pig IV-DKPGD2-Induced Peripheral Blood Leukocyte Influx

The compounds ability to inhibit leukocyte migration in vivo was assessed using intravenous injection of 13,14-dihydro-15-keto-prostaglandin D2 (DK-PGD2). Methods were adapted from those detailed Shichijo et al., 2003, Journal of Pharmacology and Experimental Therapeutics, 307:518-525. Male Hartley guinea pigs were immunized with ovalbumin (OVA) on day 0 by intraperitoneal (IP) injection of 1 ml of a 100 μg/ml solution in Imject Alum. They were then used in the DK-PGD2 procedure between days 14 and 21. Subjects were randomly assigned to receive either vehicle (0.5% methyl cellulose, 4 ml/kg, oral (PO)) or one of three to four doses of test compound. Two hours or eighteen hours after dosing, animals were anesthetized with ketamine and challenged with DK-PGD2 (1 mg/kg, IV). Thirty minutes after IV administration, blood was collected via the marginal ear vein into EDTA tubes for cell analysis. 10 μl blood was lysed in 190 μl water followed by a further 20-fold dilution in PBS. A 10 μl fraction was mixed with equal parts trypan blue and loaded on a hemocytometer. Cells were visualized at a magnification of 40× using a LabPro light microscope and totals counted and recorded. Cells are expressed as total cells×10⁸ per ml of blood. Inhibition of this effect by select compounds is determined statistically using Graphpad prism.

The compounds that were tested in Table 1 had IC₅₀ below 20 μM in the CRTH2 binding assay.

TABLE 4 Representative Biological Data hDP2 GTPγS μM Compound # hDP2 μM hDP1 μM (+HSA) 1-1 A C A 1-2 A C A 1-4 A C A 1-10 A C A 1-11 A C A 1-12 A C A 1-23 A C A 1-27 A C A 1-28 A C A 1-29 A C A 1-30 A C A 1-31 A C A 1-32 A C A 1-33 A C A 1-34 A C A 1-35 A B A 1-36 A C A 1-37 C C — 1-38 A C A 1-39 A C A 1-40 A C A 1-41 A C A 1-42 A C A 1-43 A C A 1-44 A C A 1-45 A C A 1-46 A C A 1-48 A C A 1-49 C C — 1-92 A C A 1-93 A C A 1-94 A C A 1-96 A C A 1-110 A C A 1-118 A C A 1-129 A C A 1-143 A B — 1-152 A C — 1-153 A C — 1-155 A C — 1-165 A C — 1-176 A C — 1-177 A C — 1-178 A C — 1-179 A C — 1-180 A C — 1-181 A C — 1-183 A C — 1-184 A C — 1-185 A C — 1-186 A C A 1-187 A C — 1-206 A — — 1-215 A — — 1-216 A — — 1-220 A — A 1-226 A — — 1-241 A — — 1-244 A — — 1-245 C — — 1-246 A — A 1-247 A — — 1-252 A — — 1-253 A — — 1-257 A — — Ramatroban B C B A = less than 0.3 μM; B = greater than 0.3 μm and less than 1 μM; C = greater than 1 μM.

Example 39 Clinical Trials in Humans

Study 1: Clinical Trial Evaluating Effect of Compound of Formula (I) on ex vivo PGD2-Induced Blood Eosinophil Shape Change

In this double-blind, randomized, placebo-controlled, single ascending dose study of Compound of Formula (I) in healthy volunteers the inhibition of ex vivo PGD2-induced blood eosinophil shape change is determined to show proof of biochemical mechanism of DP2 receptor antagonism. Eight subjects (6 active, 2 placebo) per dose level are used. Pre dose blood is drawn and challenged with PGD2 to determine baseline shape change as described above in Example 36. At varying times after dosing blood is drawn for both pharmacokinetic analyses of drug concentration in blood, and also for PGD2 challenge and eosinophil shape change determination. The extent of receptor blockage is determined from the relationship between drug blood concentration and percentage inhibition of eosinophil shape change.

Study 2: Clinical Trial Evaluating Effect of Compound of Formula (I) on Allergen-induced Nasal Symptoms and Inflammatory and Allergic Biomarkers

In this double-blind, randomized, placebo-controlled study of Compound of Formula (I) in individuals with allergic rhinitis the inhibition of nasal symptoms and allergic biomarkers is determined following nasal challenge with appropriate allergen. Fifteen subjects (10 active, 5 placebo) are used. Subjects are dosed for 7 days with either placebo or an amount of compound of formula (I) that results in complete DP2 receptor block in an ex vivo PGD2-induced blood eosinophil shape change pharmacodynamic study as described above. On day 7 subjects undergo nasal allergen challenge (2 hours post-dose) and early allergic response (0.25-1.0 hr) and late allergic response (4-24 hr) are evaluated as an increase from baseline for treated vs placebo. In addition changes in inflammatory cell differentials, TH2 cytokines and other inflammatory markers are determined as increase from baseline for treated vs placebo.

Compound of Formula (I) Assay

The plasma concentrations of compound of Formula (I) are determined by gas chromatography, giving a detection limit of 1 ng·ml-1 (Ritter W. Determination of BAY u 3405, a novel thromboxane antagonist, in plasma and urine by HPLC and GC. In: Reid E, Wilson ID, eds. Bioanalytical Approaches for Drugs, Including Anti-asthmatics and Metabolites. Methodological Surveys in Biochemistry and Analysis, 1992; 22: 211-216).

Example 40a Parenteral Composition

To prepare a parenteral pharmaceutical composition suitable for administration by injection, 100 mg of a water-soluble salt of a compound of Formula (I) is dissolved in DMSO and then mixed with 10 mL of 0.9% sterile saline. The mixture is incorporated into a dosage unit form suitable for administration by injection.

Example 40b Oral Composition

To prepare a pharmaceutical composition for oral delivery, 100 mg of a compound of Formula (I) is mixed with 750 mg of starch. The mixture is incorporated into an oral dosage unit for, such as a hard gelatin capsule, which is suitable for oral administration.

Example 40c Sublingual (Hard Lozenge) Composition

To prepare a pharmaceutical composition for buccal delivery, such as a hard lozenge, mix 100 mg of a compound of Formula (I) with 420 mg of powdered sugar mixed, with 1.6 mL of light corn syrup, 2.4 mL distilled water, and 0.42 mL mint extract. The mixture is gently blended and poured into a mold to form a lozenge suitable for buccal administration.

Example 40d Fast-Disintegrating Sublingual Tablet

A fast-disintegrating sublingual tablet is prepared by mixing 48.5% by weigh of a compound of Formula (I), 44.5% by weight of microcrystalline cellulose (KG-802), 5% by weight of low-substituted hydroxypropyl cellulose (50 μm), and 2% by weight of magnesium stearate. Tablets are prepared by direct compression (AAPS PharmSciTech. 2006;7(2):E41). The total weight of the compressed tablets is maintained at 150 mg. The formulation is prepared by mixing the amount of compound of Formula (I) with the total quantity of microcrystalline cellulose (MCC) and two-thirds of the quantity of low-substituted hydroxypropyl cellulose (L-HPC) by using a three dimensional manual mixer (Inversina®, Bioengineering AG, Switzerland) for 4.5 minutes. All of the magnesium stearate (MS) and the remaining one-third of the quantity of L-HPC are added 30 seconds before the end of mixing.

Example 40e Inhalation Composition

To prepare a pharmaceutical composition for inhalation delivery, 20 mg of a compound of Formula (I) is mixed with 50 mg of anhydrous citric acid and 100 mL of 0.9% sodium chloride solution. The mixture is incorporated into an inhalation delivery unit, such as a nebulizer, which is suitable for inhalation administration.

Example 40f Rectal Gel Composition

To prepare a pharmaceutical composition for rectal delivery, 100 mg of a compound of Formula (I) is mixed with 2.5 g of methylcelluose (1500 mPa), 100 mg of methylparapen, 5 g of glycerin and 100 mL of purified water. The resulting gel mixture is then incorporated into rectal delivery units, such as syringes, which are suitable for rectal administration.

Example 40 g Topical Gel Composition

To prepare a pharmaceutical topical gel composition, 100 mg of a compound of Formula (I) is mixed with 1.75 g of hydroxypropyl celluose, 10 mL of propylene glycol, 10 mL of isopropyl myristate and 100 mL of purified alcohol USP. The resulting gel mixture is then incorporated into containers, such as tubes, which are suitable for topicl administration.

Example 40h Ophthalmic Solution Composition

To prepare a pharmaceutical opthalmic solution composition, 100 mg of a compound of Formula (I) is mixed with 0.9 g of NaCl in 100 mL of purified water and filterd using a 0.2 micron filter. The resulting isotonic solution is then incorporated into ophthalmic delivery units, such as eye drop containers, which are suitable for ophthalmic administration.

Example 40i Nasal Spray Solution

To prepare a pharmaceutical nasal spray solution, 10 g of a compound of Formula (I) is mixed with 30 mL of a 0.05M phosphate buffer solution (pH 4.4). The solution is placed in a nasal administrator designed to deliver 100 of spray for each application.

The examples and embodiments described herein are for illustrative purposes only and various modifications or changes suggested to persons skilled in the art are to be included within the spirit and purview of this application and scope of the appended claims. 

1. A compound having the structure of Formula (I) or pharmaceutically acceptable salt thereof:

wherein, R⁴ is H, halogen, —CN, —OH, C₁-C₄alkyl, C₁-C₄alkoxy, C₁-C₄fluoroalkyl, C₁-C₄fluoroalkoxy, or C₁-C₄heteroalkyl; R⁵ is H, halogen, —CN, —NO₂, —OH, —S(═O)₂R¹², —NHS(═O)₂R¹², —C(═O)R¹², —OC(═O)R¹², —CO₂R^(—, —N(R) ¹³)₂, —C(═O)N(R¹³)₂, —NHC(═O)R¹², —C(OH)(R¹³)₂, C₁-C₄alkyl, C₁-C₄fluoroalkyl, C₁-C₄fluoroalkoxy, C₁-C₄alkoxy, C₁-C₄heteroalkyl, or —S—R¹²; R²⁰ is C₁-C₄alkyl, C₃-C₆cycloalkyl, —CH₂O—C₁-C₄alkyl, —CH₂O-(substituted or unsubstituted phenyl), —CH(CH₃)—O-(substituted or unsubstituted phenyl), —C(CH₃)₂—O-(substituted or unsubstituted phenyl), —CH₂OCH₂-(substituted or unsubstituted phenyl), —OC₁-C₄alkyl, —O—CH₂-(substituted or unsubstituted phenyl), —O—CH(CH₃)-(substituted or unsubstituted phenyl), —NR¹⁶C₁-C₄alkyl, —NR¹⁶—CH₂-(substituted or unsubstituted phenyl), or —NR¹⁶—CH(CH₃)-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from halogen, —OH, —OCH₃, C₁-C₄alkyl, and —CF₃; R¹⁶ is H or C₁-C₄alkyl; R¹¹ is —CH₃, —CH₂CH₃, —CF₃, —CH₂CF₃, cyclopropyl, cyclobutyl, or cyclopentyl R¹² is C₁-C₄alkyl, C₁-C₄heteroalkyl, or C₁-C₄fluoroalkyl; each R¹³ is independently selected from H, C₁-C₄alkyl, C₁-C₄heteroalkyl, and C₁-C₄fluoroalkyl.
 2. The compound of claim 1, wherein R⁴ is H, F, Cl, Br, —OH, —CH₃, —OCH₃, —CF₃, or —OCF₃; R⁵ is H, halogen, —CN, —NO₂, —OH, —S(═O)₂CH₃, —NHS(═O)₂CH₃, —C(═O)CH₃, —OC(═O)CH₃, —CO₂H, —CO₂CH₃, —CO₂CH₂CH₃, —NH₂, —C(═O)NH₂, —NHC(═O)CH₃, —CH₃, —CF₃, —OCF₃, —OCH₃, —CH₂OH, or —C(CH₃)₂OH.
 3. The compound of claim 2, wherein: R²⁰ is —CH₃, —CH₂CH₃, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, —CH₂OCH₃, —CH₂O-(substituted or unsubstituted phenyl), —CH(CH₃)—O-(substituted or unsubstituted phenyl), —C(CH₃)₂—O-(substituted or unsubstituted phenyl), —CH₂OCH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.
 4. The compound of claim 3, wherein: R₂₀ is —CH₃, cyclopropyl, —CH₂OCH₃, —CH₂O-(substituted or unsubstituted phenyl), —CH₂OCH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.
 5. The compound of claim 2, wherein: R²⁰ is —OC₁-C₄alkyl, —O—CH₂-(substituted or unsubstituted phenyl), or —O—CH(CH₃)-(substituted or unsubstituted phenyl); wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.
 6. The compound of claim 5, wherein: R²⁰ is —O—CH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, and Br.
 7. The compound of claim 6, wherein the compound has the following structure:

wherein, n is 0, 1, or 2; R⁴ is F, Cl, Br, —CH₃, —OCH₃, —CF₃, or —OCF₃; R⁵ is F, Cl, Br, —CH₃, —CF₃, —OCF₃, or —OCH₃; R¹¹ is —CH₃, —CH₂CH₃, or —CH₂CF₃.
 8. The compound of claim 2, wherein: R²⁰ is —NR¹⁶C₁-C₄alkyl, —NR¹⁶—CH₂-(substituted or unsubstituted phenyl), or —NR¹⁶—CH(CH₃)-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃; R¹⁶ is H, —CH₃, or—CH₂CH₃.
 9. The compound of claim 8, wherein: R²⁰ is —NH—CH₂-(substituted or unsubstituted phenyl), wherein if the phenyl of R²⁰ is substituted, then the phenyl is substituted with 0, 1, or 2 R²¹ groups; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.
 10. The compound of claim 9, wherein the compound has the following structure:

wherein, n is 0, 1, or 2; R⁴ is F, Cl, Br, —CH₃, —OCH₃, —CF₃, or —OCF₃; R⁵ is F, Cl, Br, —CH₃, —CF₃, —OCF₃, or —OCH₃; R¹¹ is —CH₃, —CH₂CH₃, or —CH₂CF₃; each R²¹ is independently selected from F, Cl, Br, —OH, —OCH₃, —CH₃, and —CF₃.
 11. The compound of claim 10, wherein: wherein, n is 0, 1, or 2; R⁴ is —OCH₃; R⁵ is —CF₃; R¹¹ is —CH₃, or —CH₂CH₃; each R²¹ is independently selected from F, Cl, and Br.
 12. A compound selected from among: {2′-[(Acetyl-methyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-1); {2′-[(Acetyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-2); (2′-{[Acetyl-(2,2-dimethyl-propyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-3); (2′-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-4); {2′-[(Acetyl-ethyl-amino)-methyl]-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-10); (2′-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-11); {2′-[(Acetyl-cyclopropyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-12); {2′-[(Ethyl-methoxycarbonyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-23); {2′-[(Benzyloxycarbonyl-methyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-27); {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-28); {2′-[(Benzyloxycarbonyl-methyl-amino)-methyl]-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-29); {2′-[(Acetyl-cyclobutyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-30); {2′-[(Acetyl-cyclopentyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-31); (2′-{[Ethyl-(2,2,2-trifluoro-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-32); {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-33); {2′-[(Benzyloxycarbonyl-cyclobutyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-34); {2′-[(Benzyloxycarbonyl-cyclopentyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-35); {2′-[(Benzyloxycarbonyl-cyclopropyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-36); 2-{[Acetyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-5′-carboxymethyl-2′-methoxy-biphenyl-4-carboxylic acid (Compound 1-37); (2′-{[(3,5-Dichloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-38); (2′-{[(2-Chloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-39); (2′-{[(3,5-Difluoro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-40); (2′-{[Ethyl-(4-fluoro-benzyloxycarbonyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-41); (2′-{[(4-Chloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-42); (2′-{[(3-Chloro-benzyloxycarbonyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-43); [2′-({[1-(4-Chloro-phenyl)-ethoxycarbonyl]-ethyl-amino}-methyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-44); (2′-{[Ethyl-(2-phenoxy-propionyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-45); (2′-{[Ethyl-(2-methoxy-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-46); (2′-{[Ethyl-(2-phenoxy-acetyl)-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-48); (2′-{[Benzyloxycarbonyl-(2,2,2-trifluoro-ethyl)-amino]-methyl}-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-49); {2′-[(Acetyl-ethyl-amino)-methyl]-4′-bromo-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-50); {4′-Acetylamino-2′-[(acetyl-ethyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-51); {2′-[(Acetyl-ethyl-amino)-methyl]-6-methyl-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-56); {2′-[(Acetyl-methyl-amino)-methyl]-6-fluoro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-58); {2′-[(Acetyl-methyl-amino)-methyl]-6-methyl-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-59); {2′-[(Acetyl-ethyl-amino)-methyl]-6-cyclopropyl-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-60); {2′-[(Acetyl-ethyl-amino)-methyl]-6,4′-bis-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-61); {2′-[(Acetyl-methyl-amino)-methyl]-4′-bromo-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-63); {4′-Acetylamino-2′-[(acetyl-methyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-64); {2′-[(Acetyl-ethyl-amino)-methyl]-6-methoxy-4′-methoxycarbonylamino-biphenyl-3-yl}-acetic acid (Compound 1-65); {2′-[(Acetyl-ethyl-amino)-methyl]-4′-methanesulfonylamino-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-66); {2′-[(Acetyl-ethyl-amino)-methyl]-4′-methanesulfonyl-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-67); {2′-[(Cyclopropoxycarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-75); [2′-(1-Ethyl-3-methyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-76); {2′-[(Cyclopropanecarbonyl-methyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-77); {2′-[(Cyclopentanecarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-78); {2′-[(Acetyl-ethyl-amino)-methyl]-6-chloro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-79); (2′-{[(2-Benzyloxy-acetyl)-ethyl-amino]-methyl}-6-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-92); [2′-({[2-(4-Chloro-phenoxy)-acetyl]-ethyl-amino}-methyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-93); [2′-(3-Benzyl-1,3-diethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-94); [2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-96); {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-6-chloro-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-110); [2′-({[2-(4-Chloro-phenoxy)-2-methyl-propionyl]-ethyl-amino}-methyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-118); {6-Benzyloxy-2′-[(benzyloxycarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-128); {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-6-ethoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-129); {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-6-cyclopropylmethoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-130); {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-143); {2′-[3-(3,4-Dichloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-152); {4′-Acetylamino-2′-[(benzyloxycarbonyl-ethyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-153); {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-methanesulfonylamino-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-155); {2′-[3-(3,5-Dichloro-benzyl)-l-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-165); {2′-[1-Ethyl-3-(4-fluoro-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-176); {2′-[3-(3-Chloro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-177); {2′-[3-(3,5-Difluoro-benzyl)-1-ethyl-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-178); (2′-{3-[(R)-1-(4-Chloro-phenyl)-ethyl]-1-ethyl-ureidomethyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-179); (2′-{3-[(S)-1-(4-Chloro-phenyl)-ethyl]-1-ethyl-ureidomethyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-180); [2′-(1,3-Diethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-181); [2′-(3-Cyclopropyl-1-ethyl-ureidomethyl)-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-182); {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-183); {2′-[(Acetyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-184); {2′-[3-(4-Chloro-benzyl)-l-ethyl-ureidomethyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-185); {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-4′-fluoro-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-186); [2′-(3-Benzyl-1-ethyl-ureidomethyl)-4′-fluoro-6-methoxy-biphenyl-3-yl]-acetic acid (Compound 1-187); {2′-[(Cyclobutanecarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-206); {2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-methanesulfonyl-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-215); [2′-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-4′-(1-hydroxy-1-methyl-ethyl)-6-methoxy-biphenyl-3-yl]-acetic acid (Compound 1-216); [2′-(3-Benzyl-1-ethyl-ureidomethyl)-6-hydroxy-4′-trifluoromethyl-biphenyl-3-yl]-acetic acid (Compound 1-220); 2-[(Benzyloxycarbonyl-ethyl-amino)-methyl]-5′-carboxymethyl-2′-methoxy-biphenyl-4-carboxylic acid (Compound 1-226); {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-6-methoxy-4′-methylsulfanyl-biphenyl-3-yl}-acetic acid (Compound 1-241); {2′-[(Cyclopropanecarbonyl-ethyl-amino)-methyl]-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-244); (2′-{[(2,2-Dimethyl-propionyl)-ethyl-amino]-methyl}-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl)-acetic acid (Compound 1-245); {2′-[(Ethyl-isobutyryl-amino)-methyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-246); {4′-Bromo-2′-[(cyclopropanecarbonyl-ethyl-amino)-methyl]-6-methoxy-biphenyl-3-yl}-acetic acid (Compound 1-247); {2′-[1-Ethyl-3-(4-hydroxy-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-252); {2′-[1-Ethyl-3-(2-hydroxy-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-253); and {2′-[1-Ethyl-3-(3-hydroxy-benzyl)-ureidomethyl]-6-methoxy-4′-trifluoromethyl-biphenyl-3-yl}-acetic acid (Compound 1-257).
 13. A pharmaceutical composition comprising a therapeutically effective amount of a compound of claim 1, or a pharmaceutically acceptable salt thereof, and at least one pharmaceutically acceptable inactive ingredient selected from pharmaceutically acceptable diluents, pharmaceutically acceptable excipients, and pharmaceutically acceptable carriers.
 14. The pharmaceutical composition of claim 13, wherein the pharmaceutical composition is formulated for intravenous injection, oral administration, inhalation, nasal administration, topical administration, ophthalmic administration or otic administration.
 15. The pharmaceutical composition of claim 13, wherein the pharmaceutical composition is a tablet, a pill, a capsule, a liquid, an inhalant, a nasal spray solution, a suppository, a suspension, a gel, a colloid, a dispersion, a suspension, a solution, an emulsion, an ointment, a lotion, an eye drop or an ear drop.
 16. A method for treating a PGD₂-dependent or a PGD₂-mediated disease or condition in a mammal comprising administering to the mammal a therapeutically effective amount of a compound of claim
 1. 17. The method of claim 16, wherein the disease or condition is a respiratory disease or condition, an allergic disease or condition, or an inflammatory disease or condition.
 18. The method of claim 16, wherein the disease or condition is asthma.
 19. The method of claim 16, wherein the disease or condition is COPD.
 20. The method of claim 16, wherein the disease or condition is allergic rhinitis. 